Engine Conundrums

Boydie · Sun Jul 23, 2023 10:12 am

Okay, those that know diesel engines and obviously in particular the 3.2 litre 5 cylinder Puma Engine, see if you can came up with a valid reason for these events.

Past history,
The ECR Cooler and the DPF was electronically deleted and physically removed at the same time - arround the 500 kilometer mark - and an oil catch can and 35 micron fuel pre-filter installed. The OE transmission cooler was replaced with an air cooled radiator at the 80,000 kilometer distance. Oil and filter services are carried out as close as possible every 10,000 k's. The 6R80 auto transmission has a "AFE" alloy deep-finned sump holding an additional 6 litres of ATF and a thermostatic by-pass valve was installed at the 50,000 k mark.

Okay.
Prior to us setting off on our intended 5 month jaunt to the NT and WA the Wildtrak started going into limp mode, there were no codes, just the dreaded orange spanner. Turn off the ignition and off it would go again for another 12 or so kilometres and then it would go back into limp mode.
At first I thought it was the autobox and dreaded a $8000 replacement bill but I made a call to Wholesale Automatics who said it was more likely to be an engine issue and advised me to go to a local specialist who they recommended.
I took it to these people who had it for a day and who called me to say the issue was fixed and that it was due to over-heated fuel as the supply and return hoses on the main fuel filter had been changed over, supply being connected to return etc.
Now, I had personally replaced the standard unions on the Western Filters pre-filter with push-on connections and with these connections fitted the previous year we had driven to the NT, went over the Gibb River Road and up to Honeymoon Bay, down to Kalgoolie and over the Great Central Road to Alice Springs and then dowwn to Port Augusta and then home - without a single incident of the engine going into limp mode.
A total distance, in summer ambient temperatures of arround 7,000 kms.
I cannot see how the supply and return hoses on the standard OE filter can be crossed over as they are different sizes and colour connections, Blue ( to and from the engine ) and Red ( to and from the fuel tank ).

So, assured that the problem was fixed and that there were no lasting issues we set off a week later, only to have the engine go - again - into limp mode on the Barrier Highway.
This wasnt consistant and so we drove to Alice Springs without any further issues. After 4 weeks and on our last day as "Hosts" at Palm Valley we drove to drop off our rubbish at Hermannsberg tip only to see clouds of white smoke pouring out of the exhaust.
We drove to Alice and the local Ford Dealer who confirmed we had a blown head gasket. The service manager told us that they could'nt do the work in Alice Springs and that we would have to have the Wildtrak transported to Darwin and it would be a 4 week turn-around due to ordering parts and their current work load. They quoted $8000.
Instead, and in desperation I poured a container of Nulon Head Gasket Sealer into the header tank, followed the instructions and wonders -- the leak was sealed and loss of coolant stopped, however the engine had developed a noticable loud "tick", this started when, on one occassion only, when I first ran it with the Nulon in the coolant system it went into "High Engine Temperature". Once it cooled down quickly from 120 C to 88 C the ticking started and has been there ever since - could it be a hydraulic lifter or injector perhaps ???
We then drove down to Port Augusta to the Ford Dealership there who while they could'nt explain the loud "tick" confirmed that as we had already driven 1300 k's from Alice the intended drive west to Kalgoorlie was possibly okay, so the following day off we went. We only lasted a week in WA due to unseasonable deplorable cold weather and returned east and home.

Okay, does anyone have any ideas as to what went wrong with the engine ?

I do not think it was "hot fuel" as we were told, and I still have that invoice with that claim. If it was hot fuel why didnt it go into limp mode during the previous summer ?
I have all the gaskets and parts to replace the blown head gasket ( $1300 worth !!) and I'll be doing this in the next week or so once I'm fully satisfied that all the Nulon product has been flushed out of the coolant system, at the same time I'll be dripping the sump and fitting a gear style oil pump to replace the standard vane style unit.

My gut feeling is that when previously the engine went into "limp" mode untimed detonations had occured that finally caused the head gasket to fail. I've experienced this type of failure with high performance petrol engines but my experience with diesels is very, very limited, but as to why it occured I have no ideas.

Bala1 · Sun Jul 23, 2023 12:56 pm

The red and blue fuel lines can be crossed. Both blue put where both red should be and visa versa. It has been mentioned many times online as a limp mode cause with no dtc.

Recently you had a post about coolant expansion, trans over heat ect. IMHO the coolant expansion is likely from air in the system after fluid drain and that air lock the start of the head gasket damage.

Vacuum coolant fill appears to be the way to ensure no air is in the system.

Boydie · Mon Jul 24, 2023 9:38 am

Bala1 wrote: ↑Sun Jul 23, 2023 12:56 pm The red and blue fuel lines can be crossed. Both blue put where both red should be and visa versa. It has been mentioned many times online as a limp mode cause with no dtc.

Recently you had a post about coolant expansion, trans over heat ect. IMHO the coolant expansion is likely from air in the system after fluid drain and that air lock the start of the head gasket damage.

Vacuum coolant fill appears to be the way to ensure no air is in the system.

Yes, I'm aware that the Red and Blue lines can be crossed, there being a Red large and small connection and a similar Blue large and small connection.

Neither had been changed or tampered with since my previous service when I changed the fuel filter, Blue lines on the engine side of the fuel filter and Red on the battery side, Blue lines to and from the mechanical fuel pump, Red to and from the fuel tank, and that service was before we went up to the NT and did the Gibb River Road and the Great Central Road from Kalgoolie up to the Stuart Highway.
I don't know that the Transmission has ever actually overheated, certainly its never thrown up a fault code even when it was using the original Ford cooler and acording to the Ultragauge its never - ever - gone over 102 degrees C, it used to run at 10-12 degrees higher than the engine coolant temperature so if the engine was at 88 degrees the ATF would be sitting on 98-100 degrees.

I certainly agree with you about the coolant system, its a real bitch to bleed, and using a vacuum certainly has merits and I'll try that once I've replaced the head gasket.

What bemuses me is the vastly various coolant fluid levels, on my Ranger when its cold its up to almost overflowing but once it gets up to running temperature its down to the "Normal" level on the header tank. In all my automotive years I've never had this experience before but then this is the first engine that runs on 21 PSI as against 13-14 PSI.

All of this is interesting but really doesnt really explain the head gasket failure though.

Bala1 · Mon Jul 24, 2023 10:25 am

To me the head gasket failure is explained.

At some point the engine has been run with an incorrectly bled cooling system.

The coolant header tank filling up when coldi is not normal, it is a sign that there is a problem.

Boydie · Mon Jul 24, 2023 2:30 pm

Bala1 wrote: ↑Mon Jul 24, 2023 10:25 am To me the head gasket failure is explained.

At some point the engine has been run with an incorrectly bled cooling system.

The coolant header tank filling up when coldi is not normal, it is a sign that there is a problem.

I think that I may have found the problem, if you can call it that.
On the thermostat housing is a small 6 mm hose that goes from the top of the housing to the top of the header tank.
The connection in this hose spigot at the housing has a small orifice - on taking the housing apart I found this orifice on mine was non existant and totally blocked, using a tiny flexible optical illuminated "eye" connected to my so called smart phone I could see that it wasnt blocked with Nulon the head gasket sealer, that is easily discernable by its orange colour - it was simply blocked and closed off with something that in colour was black and is a very hard material.
I'd guess this orifice, which appears to be in a brass insert that is cast into the plastic housing, would be 1- 2mm at the most in diameter and I'm guessing that this small orifice allows the system to vent air from the engine block to the header tank and to equalise the system pressure. Its location is directly above and to the rear of the thermostat popple ball valve.
There is no way of me telling just how long this orifice has been blocked but I can honestly say that I've never ever seen any coolant being discharged from this hose into the header tank, which you would expect if it was venting air and equalising system pressures.
Due its small size it could easily be blocked by a tiny piece of production debris, casting sand etc. - I've ordered a new housing - $145 !!! and once I've taken delivery of it I'll see if I can guestimate the diameter that its supposed to be and then drill this one out and put it in my "spares" locker.
If it was too big it would negate the correct operation of the thermostat by-pass valve, too small and it could possibly prevent correct system venting etc.
Only Ford could come up with a coolant system as complex as this one.

Davros · Mon Aug 07, 2023 10:32 pm

Boydie wrote: ↑Mon Jul 24, 2023 2:30 pm
Bala1 wrote: ↑Mon Jul 24, 2023 10:25 am To me the head gasket failure is explained.

At some point the engine has been run with an incorrectly bled cooling system.

The coolant header tank filling up when coldi is not normal, it is a sign that there is a problem.
I think that I may have found the problem, if you can call it that.
On the thermostat housing is a small 6 mm hose that goes from the top of the housing to the top of the header tank.
The connection in this hose spigot at the housing has a small orifice - on taking the housing apart I found this orifice on mine was non existant and totally blocked, using a tiny flexible optical illuminated "eye" connected to my so called smart phone I could see that it wasnt blocked with Nulon the head gasket sealer, that is easily discernable by its orange colour - it was simply blocked and closed off with something that in colour was black and is a very hard material.
I'd guess this orifice, which appears to be in a brass insert that is cast into the plastic housing, would be 1- 2mm at the most in diameter and I'm guessing that this small orifice allows the system to vent air from the engine block to the header tank and to equalise the system pressure. Its location is directly above and to the rear of the thermostat popple ball valve.
There is no way of me telling just how long this orifice has been blocked but I can honestly say that I've never ever seen any coolant being discharged from this hose into the header tank, which you would expect if it was venting air and equalising system pressures.
Due its small size it could easily be blocked by a tiny piece of production debris, casting sand etc. - I've ordered a new housing - $145 !!! and once I've taken delivery of it I'll see if I can guestimate the diameter that its supposed to be and then drill this one out and put it in my "spares" locker.
If it was too big it would negate the correct operation of the thermostat by-pass valve, too small and it could possibly prevent correct system venting etc.
Only Ford could come up with a coolant system as complex as this one.

The piece of “stuff” isn’t a bit of head gasket? My Land Rover TD5 engine would pressurise the cooling system and eventually blow fluid out of the reservoir when the head gasket had blown. Another symptom was difficulty starting - seemed like the starter motor would stall. In hindsight it was fluid in the cooling system being dripped into the cylinder when the engine was off and hydraulic action then stopped it turning over easily. The gasket leak was definitely more one-way though (into the cooling system) and I think the gasket blew in a way that acted like a duck-billed one-way valve. Early TD5 engines blew head gaskets due to use of plastic head dowels that eventually allowed movement. I wonder what the ranger has to keep things aligned?
I would give just as much weight to the bit of stuff in that pipe being a result of the fault than a cause…

Boydie · Wed Aug 09, 2023 8:50 am

"The piece of “stuff” isn’t a bit of head gasket? My Land Rover TD5 engine would pressurise the cooling system and eventually blow fluid out of the reservoir when the head gasket had blown. Another symptom was difficulty starting - seemed like the starter motor would stall. In hindsight it was fluid in the cooling system being dripped into the cylinder when the engine was off and hydraulic action then stopped it turning over easily. The gasket leak was definitely more one-way though (into the cooling system) and I think the gasket blew in a way that acted like a duck-billed one-way valve. Early TD5 engines blew head gaskets due to use of plastic head dowels that eventually allowed movement. I wonder what the ranger has to keep things aligned?
I would give just as much weight to the bit of stuff in that pipe being a result of the fault than a cause…"

I used a fine pin punch to carefully press the bit of "grit" out of the brass orifice and it's definitely ceramic in nature, my best guess being that its a grain of casting sand from the cylinder block or head. Either way it's now in my "Woefull Faulty Parts" museum immersed in water in a small glass sample jar, a tiny speck of black material that has cost me well over $2000 and still counting.
I dont think its part of the cylinder head gasket as its a case of what came first, the chicken and the egg. First there had to be a blockage in the vent line then the cylinder head gasket uncooled would have failed, not the other way around.
Prior to buying the Ranger in 2017 I had a Disco, a 300Tdi Series 1 that we did 865,000 kms in during our 20+ years of ownership and driving it all over Australia so I fully understand all Land Rover issues and have lots of sympathy.

fgturbofan · Wed Aug 16, 2023 7:43 pm

Unfortunately the tick will be the fact the piston has grabbed the bore. I have a p5at engine sitting on the floor at work with a similar story behind it.
Split coolant hose, got hot, started to tick , I just haven't had the chance to pull it down and inspect it properly, the customer insisted on fitting a new engine from ford for a quick turn around.
I would be removing the engine and pulling it down. Do the oil pump at the same time and maybe research some piston skirt coatings for the new build.
I have been following your troubles on different platforms and with the preventative maintenance you have preformed I'm a little disappointed that your engine failed.

Boydie · Thu Aug 17, 2023 9:38 pm

fgturbofan wrote: ↑Wed Aug 16, 2023 7:43 pm Unfortunately the tick will be the fact the piston has grabbed the bore. I have a p5at engine sitting on the floor at work with a similar story behind it.
Split coolant hose, got hot, started to tick , I just haven't had the chance to pull it down and inspect it properly, the customer insisted on fitting a new engine from ford for a quick turn around.
I would be removing the engine and pulling it down. Do the oil pump at the same time and maybe research some piston skirt coatings for the new build.
I have been following your troubles on different platforms and with the preventative maintenance you have preformed I'm a little disappointed that your engine failed.

Finally the head will come off tomorrow or Saturday latest.

I think you are right about a piston as there is no evidence of there ever having been any water in the engine, no sludge in the rocker cover and none in the engine oil.
I have a gear oil pump on order so the sump will be coming off.
The engine was tested in Alice Springs by Ford and I was told that all 5 cylinders were to specification compression wise so it will be interesting once the head comes off.
The coolant system was pressure tested by them for 4 hours at 21 psi with no drop in pressure but once the engine was run up to temperature it showed a slight drop in pressure, very odd.

The injectors are ready for collection and have been tested and are almost as good as new, not bad for a 155,000 km engine and better still they do not need replacing.

One thing I noticed in the dismantle process, the flange to turbo connection joint, there was no gasket, ( metal or composite material ) and the two ports were not aligned/ mated, the exhaust manifold diameter being at least 15% smaller than the turbo. The offset was quite obvious once the two were seperated.
Using a tool makers grinder I have mated / matched the two so that they are "flowed" and removed all the built-up carbon in the exhaust manifold.

The main delays in the dissasembly were :-
I'm 75 and no longer as agile as I used to be !!
The 10mm bolt bolding the turbo heat shield was seized solid and I had to cut the bracket to remove the heat shield.
The large 10.8 high tensile bolt holding the engine mount to the engine bracket was also seized.
The nut retaining the engine mount to the chassis is directly above the right hand CV joint making it almost impossible to put a decent spanner or socket onto it.
I was able to remove, complete and in one piece the EGR Cooler and EGR valve assembly, I doubt if it will be re-installed !!

Boydie · Thu Aug 24, 2023 10:46 am

I'm beginning to think that Gud Lul is a chinaman and that at some time in my dim and distant past he wished me an eventfull life !!
Okay, so I purchased the special "spanner" to undo the three crank shaft bolts that hold the pulley onto the crankshaft.. This item has three holes, two at any time fit over two of the bolts to hold it and prevent it from turning and for the third there is a hole drilled in the spanner to allow a 15mm socket to slide over the third bolt to allow a wrench or breaker bar to undo the bolt. Once loosened you go onto the next bolt etc.
Okay so bolt No.1 came loose and I was able to screw it in and out with my fingers, bolts two and three however - no such luck !! Both are in so tight that the flats on the 15mm bolt head became rounded and the socket just turned on them

my next "approach" has been to fill the socket with plastic steel to see if the bolt will now turn once the compound has had time to fully set, failing that the only other option will be to tack weld an old socket to the bolt head flange.
Life was never meant to be easy !!

Boydie · Sat Aug 26, 2023 8:22 am

The saga, for those of you who have been following this sorry tale, continues unabated.
The only way for me to undo the two remaining crank bolts was to tack-weld a 15mm socket to the bolt head(s) and then unscrew them. On talking to the service manager at my local Ford stealership they remove the entire engine, lock the flywheel and then use an air powered two handled impact wrench to undo these bolts !!! I'm told that undoing the flywheel/flexplate bolts present a similar hassle.
Okay, so the head is off and it would seem that there is a possible broken ring in No-3 cylinder- going by the scoring in the exhaust side of the bore.
Ford (of course) do not sell 3.2 litre Puma 5 cylinder engine pistons, or piston rings. They only sell a "short motor" for the measly price of $3595.00 inc GST !!! and these are on a 3-4 month waiting list !!! Luckily though Repco do sell the pistons, standard size and three over sizes up to 0.0070mm and these are telflon coated and they supply matching ring sets for under a grand. Its a pity they dont sell them with ceramic coated heads. Guess where I'll be going for new pistons and rings.
Honing the bore(s) may be an issue. I dont think that I will be able to completely remove all traces of the scoring but as the motor was'nt using any oil prior to the strip-down and the engine oil pressure was still at 45-50 psi -- as it was from new -- I dont think the scores are a real issue, however the vane oil pump will be replaced though with a gear style pump.
Interestingly enough the original honing marks were evident in all five cylinders - not bad for 155,000 kms.
One thing I've noted is that there is no drain in the block ! So water/coolant is still in the bottom of the block so I may end up drilling a hole and tapping it with say a 3/8 BSP plug to provide a low level drain point.

Boydie · Sun Aug 27, 2023 8:56 am

Okay, so the issue has been finally detected, as I said there is some vertical scoring in No.3 piston.
This is possibly due to a cracked or broken compression ring however due to the alloy sump extension plate there is no way of undoing the No.3 conrod without removing the engine.
So I'll be putting it all back together as it is. I've ordered a set of +.0.004 pistons and rings and in due course I'll get my local mechanic to pull the motor out and have it re-bored before next August when we depart for our annual foray to the NT and WA doing our National Parks Hosting stints.
We drove well over 6000 kms from Kalgoolie in WA to home in NSW with the engine the way it is and towing our 2.3 tonne off-road camper-trailer so I have every confidence that it will be okay for local runs until then, if it gets any worse there are several products on the market such as STP that will aid in reducing any high oil consumption.
I'm already planning to have a few things carried out during the re-build process, one is to have the block chemically cleaned and have a 1/2" NPT drain pug tapped into the water jacket on the right hand side - ( the easy access side ) - so that all the coolant can be easily drained out when full coolant replacement is due and I'm also thinking of having the engine block powder coated or two pack painted, I'm thinking bright yellow or green

fgturbofan · Sun Aug 27, 2023 7:47 pm

Honestly you should just pull the engine now, its already half way there.
I'm pretty sure Engines Australia sell hard parts like pistons , rod bearings etc for a no doubt cheaper price then Repco.
Take it too a reputable machine shop and get them to assemble a long motor for you.
As you would know assembling the cylinder head to that vehicle is a pain , I've done a couple and its actually easier fitting a engine.
Also you need to be replacing the high pressure fuel pump, or at minimum getting it send away and tested, They are known for breaking the internal springs which puts metal through the injectors and also when the break springs the pump has to work harder which in turn elevates fuel temperature and causes limp mode with no codes , similar to your first post.

Boydie · Mon Aug 28, 2023 10:08 am

fgturbofan wrote: ↑Sun Aug 27, 2023 7:47 pm Honestly you should just pull the engine now, its already half way there.
I'm pretty sure Engines Australia sell hard parts like pistons , rod bearings etc for a no doubt cheaper price then Repco.
Take it too a reputable machine shop and get them to assemble a long motor for you.
As you would know assembling the cylinder head to that vehicle is a pain , I've done a couple and its actually easier fitting a engine.
Also you need to be replacing the high pressure fuel pump, or at minimum getting it send away and tested, They are known for breaking the internal springs which puts metal through the injectors and also when the break springs the pump has to work harder which in turn elevates fuel temperature and causes limp mode with no codes , similar to your first post.

It's all a question of time and of course money and the fact that the Wildtrak is in a neighbours shed and in its location its neigh on impossible to get it out without it being driven.
I have already a spare full set of gaskets, excepting the cylinder head gasket - and as I said previously the injectors have been tested and are okay, The high presure fuel pump was sent away to be tested and is also okay and is ready for collection today. The OE vane oil pump has been replaced with a gear style unit and doing it this way it gives me time to save up a few sheckles towards the cost of the re-bore.
I'm still deciding on +.0040 or +.0070 oversize pistons though, I think the .00040 should be more than suficient and as the existing head gasket is a 2 hole item I can have the head skimmed and go for a 3 hole head gasket. A new timing chain and cogs will be on the list as well.

Boydie · Fri Sep 01, 2023 7:57 am

Okay, I've made the decision and I'll go for the Ford Short motor at $3500.
The reason is purely fiscal.
A set of +002 pistons and rings will set me back $2200 on top of that there would be the costs of bearings, (mains and big ends $1200) and of course the re-bore so a Ford short motor at $3500 makes economic sense and they are readily available.
For the $3500 you get a new block, fully assembled with pistons, crank, con-rods and bearings. You still have to use your own original cylinder head, timing cover and timing chain, fuel pump, oil pan, oil pump, turbo etc. I'll still be fitting a low level coolant drain plug though.
The labour costs to pull the motor out reassemble it and put it back in will be reduced as they will be fewer assembly hours.
This is a time for some regrets and kicking my back-side as you may recall last year I built a "spare long motor" as a winter man-shed hobby and then out of compassion for another desperate Ranger owner I sold it to him, I wont be doing that again in a hurry !!

Fri Sep 15, 2023 4:06 pm

You have a lot of patience, I would have sold it ages ago
The worst thing is the motor you are putting in will have the same piston failure issue as the motor you take out
There is a shortage of these motors for a reason
A 3.2 from a PX1 with 240,000 klms on it recently sold for $7,000, have to be desperate
Never known a vehicle like the Ranger, people just keep on spending money on them to try to make them reliable

Boydie · Mon Sep 25, 2023 8:39 am

RossPat wrote: ↑Fri Sep 15, 2023 4:06 pm You have a lot of patience, I would have sold it ages ago
The worst thing is the motor you are putting in will have the same piston failure issue as the motor you take out
There is a shortage of these motors for a reason
A 3.2 from a PX1 with 240,000 klms on it recently sold for $7,000, have to be desperate
Never known a vehicle like the Ranger, people just keep on spending money on them to try to make them reliable

According to Simnclare Ford in Penrith Ford in Melbourne stock levels show that they have 80 "short engines" in stock and have another 30 on back order. So supply isnt an issue and there certainly isnt the shortage of them as you indicated, currently, if I won lotto tomorrow a possible delivery to my front door is around 3 days however coming up with the $3,500 for the motor and I'd estimate another $2,000 for parts and labour to get it installed is an issue.
Even with the scored bores in the bottom of Nos. 2 & 3 cylinders the engine is running perfectly okay with no major compression drop, all are within 5% of each other but I'll be using some Nulon Heavy Diesel addative when I do the next oil change to see if it makes any improvement - the clicking noise from the two cylinders is an annoyance.
The motor used to use on average around 100ml of oil per 3000 kms, the maximum permitted is 100ml per 1000 kms. and I'd guestimate that this will now go up to around 200ml even thoiugh there is no oil smoke or smell at the exhaust. This volume is including the oil and condensate discharged from the oil catch can, around 250ml every 40,000 kms as per the recommended drain and filter change period.

Boydie · Mon Sep 25, 2023 8:46 am

RossPat wrote: ↑Fri Sep 15, 2023 4:06 pm You have a lot of patience, I would have sold it ages ago
The worst thing is the motor you are putting in will have the same piston failure issue as the motor you take out
There is a shortage of these motors for a reason
A 3.2 from a PX1 with 240,000 klms on it recently sold for $7,000, have to be desperate
Never known a vehicle like the Ranger, people just keep on spending money on them to try to make them reliable

Why will the new motor have the same piston failure issues as the current one ??
The failure on this occassion was caused by the blocked engine vent. The chances of this happening again are very remote indeed especially as its something that I will be looking out for regulary by checking that the vent line is hot and that coolant fluid is flowing through it to the header tank.
You also have one so its either a case of its the best engine chassis combination going or that there is no acceptable alternative on the market in the same price range.

Mon Sep 25, 2023 3:19 pm

Boydie wrote: ↑Mon Sep 25, 2023 8:46 am
RossPat wrote: ↑Fri Sep 15, 2023 4:06 pm You have a lot of patience, I would have sold it ages ago
The worst thing is the motor you are putting in will have the same piston failure issue as the motor you take out
There is a shortage of these motors for a reason
A 3.2 from a PX1 with 240,000 klms on it recently sold for $7,000, have to be desperate
Never known a vehicle like the Ranger, people just keep on spending money on them to try to make them reliable
Why will the new motor have the same piston failure issues as the current one ??
The failure on this occassion was caused by the blocked engine vent. The chances of this happening again are very remote indeed especially as its something that I will be looking out for regulary by checking that the vent line is hot and that coolant fluid is flowing through it to the header tank.
You also have one so its either a case of its the best engine chassis combination going or that there is no acceptable alternative on the market in the same price range.

The motor design hasn't changed, I have no idea how many Rangers have had #3 fail but it would be thousands and I doubt they all had a blocked vent.
Rangers don't like heat so don't tow in hot weather
Larger radiators will not stop it happening.
I was referring to long motors, not short.

Boydie · Tue Sep 26, 2023 9:20 am

The motor design hasn't changed, I have no idea how many Rangers have had #3 fail but it would be thousands and I doubt they all had a blocked vent.
Rangers don't like heat so don't tow in hot weather
Larger radiators will not stop it happening.
I was referring to long motors, not short.
[/quote]

The "fragility" of No.3 piston & it's cylinder is due to the short exhaust manifold design and the resulting close proximity to the turbo inlet. The exhaust gas escapes too quickly resulting in high internal temperature changes. One solution to that is, as Ford has done, is to locate an Exhaust Gas Temperature Sensor in the port to limit / control the exhaust gas temperatures by putting the engine into a limp mode if ever the EGT rises above an acceptable limit.
The other consideration is that if the engine does over-heat, as mine did, the central pistons , 2;3;4 have a tendancy to "grip" their bores.
I'd have to spend some time studying and measuring the internals of the engine but I'm of the opinion that this tendancy to "grab" the bores is also due to the degree of the off-set of the Puma crankshaft, but most engines will do this, years ago in the early 1980's Land Rover solved the same problem by coating their 300 Tdi series pistons with teflon which fixed the problem but almost doubled the manufactured cost per piston.
As for towing in hot weather. Although I have a defective and leaking Koyorad Radiator that has to be replaced ( one from Aussie Desert Coolers come to mind ) some time ago when I first installed the Koyorad I fitted several Heraeus thermocouples to varions places and, on a 38 a degree ambient temperature day I recorded that it had a top header temperature of 89 degrees C at the top supply hose connection, the borrom "header" close to the return hose connection the temperature was down to 52 degrees and 55 degrees at the supply manifold to the engine. My Ultragauge showed the temperature at the water temperature sensor at 89 degrees. A sensor located on the bottom of the RH drivers side of the radiator was at a very low 42 degrees !! This is the "dead" area as the coolant flow goes into the top centre and exits bottom left. The bottom right is the top-up from the header tank, there is very little flow on the RH side towards the return.
If there were room a couple of "T" pieces and a hose connecting the existing top up port to the return hose to the coolant pump could possibly be a good idea in mixing up the diverse radiator temperatures.