Jcb Perkins presurising

[eyetee]

I’ve exhausted my knowledge with this issue, needing some help.
2003 Jcb 540-70 4cyl Perkins turbo engine only done 2000hrs

Symptom was is presurising cooling system and ejecting fluid out of expansion tank. Neither oil or coolant contaminated. I replaced the head gadget last year, cleaned both surfaces and with a straight edge appeared sound. Rad is clear and sound, water pump, thermostat sound, pipe between expansion tank and thermostat housing sound. It lasted a few months before problem returned. Limped around throughout the summer, kept revs down, it doesn’t get hot. Not smoking excessively.

Stripped head off again, had it pressure tested its come back clear, it’s now getting a light skim. Don’t really want to take the block out. I’ve also tested the oil cooler.

Is there something I am overlooking that could be the causing problem????

[Footsfitter]

Has got one of the bypass type thermostats? (or has it the machined hole below the stat to take one)?

If it was a bypass type system then a problem there in the stat area may keep circulation going round the head and not much around the block......

[essexpete]

Too late now but there is a kit that will detect combustion gases.

[eyetee]

Has got one of the bypass type thermostats? (or has it the machined hole below the stat to take one)?

If it was a bypass type system then a problem there in the stat area may keep circulation going round the head and not much around the block......

The thermostat in its housing is old school when closed prevents any flow, there is a small pipe that allows some return to the expansion tank. I checked thermostat was functioning before the first time it came apart.

[eyetee]

Too late now but there is a kit that will detect combustion gases.

Yup forgot to mention first time round I checked gases and it turned blue indicator yellow, suggesting combustion gases present. This time round it didn't.

[Masseyman1982]

I think there was an issue on these with the fuel injection pump causing it to pressurise th header tank and in some cases blow the header tank

[eyetee]

I think there was an issue on these with the fuel injection pump causing it to pressurise th header tank and in some cases blow the header tank

Interesting do you know where I can find more detail?

[Footsfitter]

I think there was an issue on these with the fuel injection pump causing it to pressurise th header tank and in some cases blow the header tank

Thought that was the diaphragm on the pump to control the turbo boost which can pressurise the fuel tank ?

[ACE]

I’ve exhausted my knowledge with this issue, needing some help.
2003 Jcb 540-70 4cyl Perkins turbo engine only done 2000hrs

Symptom was is presurising cooling system and ejecting fluid out of expansion tank. Neither oil or coolant contaminated. I replaced the head gadget last year, cleaned both surfaces and with a straight edge appeared sound. Rad is clear and sound, water pump, thermostat sound, pipe between expansion tank and thermostat housing sound. It lasted a few months before problem returned. Limped around throughout the summer, kept revs down, it doesn’t get hot. Not smoking excessively.

Stripped head off again, had it pressure tested its come back clear, it’s now getting a light skim. Don’t really want to take the block out. I’ve also tested the oil cooler.

Is there something I am overlooking that could be the causing problem????

I think these were bad for expansion tank leaking on the plastic weld seam were the 2 halves join. You sure its not just that?

Thermostat does close off the bypass and for what they cost just chuck a new one in.

Its an 1100series engine i assume being a 2003? So they have very thin wall cylinder bores and an open deck design which do not like over heating much.

[T P]

Assuming it is Ace indicated is an 1100 series from page 58 of the manual:



If someone has lost the locating dowels for the gasket (seen that, they get removed in an overhaul and forgotten) or the temporary locating studs aren't used it's Russian roulette as to whether the gasket seals as it may or may not be concentric wit the fire ring on the liners. I have personally seen and repaired failures because of this. Are you are the first one in there? Has the head been skimmed before? etc etc. Is the liner height correct if spurious parts were used in the past? Some engines blow gasket after gasket but there's always a reason if you dig deep enough and it's usually a previous visitors screw up.

[eyetee]

I think these were bad for expansion tank leaking on the plastic weld seam were the 2 halves join. You sure its not just that?

Thermostat does close off the bypass and for what they cost just chuck a new one in.

Its an 1100series engine i assume being a 2003? So they have very thin wall cylinder bores and an open deck design which do not like over heating much.

Expansion tank is good, the coolant is coming out of the cap.
Yes the cylinder walks are all joined together with a water jacket around the lot
Tested the thermostat and it opens, engine was gassing up before it got hot.

[eyetee]

Assuming it is Ace indicated is an 1100 series from page 58 of the manual:



If someone has lost the locating dowels for the gasket (seen that, they get removed in an overhaul and forgotten) or the temporary locating studs aren't used it's Russian roulette as to whether the gasket seals as it may or may not be concentric wit the fire ring on the liners. I have personally seen and repaired failures because of this. Are you are the first one in there? Has the head been skimmed before? etc etc. Is the liner height correct if spurious parts were used in the past? Some engines blow gasket after gasket but there's always a reason if you dig deep enough and it's usually a previous visitors screw up.

Locating dowels are still in the block, I can imagine it would be a lottery getting gadget square if they werent.
I think I am the first ink the engine, it’s been on the farm since 2013 and only became an issue in 2017.
A square edge showed cylinder walls to be level, skimmed 7mm off of the head.

It’s going back together now.

[ACE]

Locating dowels are still in the block, I can imagine it would be a lottery getting gadget square if they werent.
I think I am the first ink the engine, it’s been on the farm since 2013 and only became an issue in 2017.
A square edge showed cylinder walls to be level, skimmed 7mm off of the head.

It’s going back together now.

7mm!!! Thats hell of a lot! Your valves will hit the pistons when they open i think!

Oh yeah check head bolts for stretch, as this could be the 3rd time they been used they could well be scrap.
Make sure they are torqued down correctly. You have a low torque setting to start off then its done by degrees and is a nasty feeling when on the final tightening stage you thing they are going to snap!

[Paw]

7mm!!! Thats hell of a lot! Your valves will hit the pistons when they open i think!

.....

I'm hoping it's a typo and should be .7

[Ironhead]

I'm hoping it's a typo and should be .7

.7 mm works out to about 1/32
7 mm works out to about 9/32

The bottom end should be able to take the compression change created by 1/32 less combustion chamber. With 9/32 if the valves didn't hit, I doubt the bottom end would take the extra strain very long.

[eyetee]

7mm!!! Thats hell of a lot! Your valves will hit the pistons when they open i think!

Oh yeah check head bolts for stretch, as this could be the 3rd time they been used they could well be scrap.
Make sure they are torqued down correctly. You have a low torque setting to start off then its done by degrees and is a nasty feeling when on the final tightening stage you thing they are going to snap!

Yes my haste 0007
When it was all back together there was a moment of panic when it spun over with no compression, started looking on the bench for forgotten bits or pipes not attached, it was the tappets.
I got a new set of bolts, 50 nm then 100 nm then 225 degrees on the short boots and 270 on the long.
She is running and no pressure at the moment.

[eyetee]

.7 mm works out to about 1/32
7 mm works out to about 9/32

The bottom end should be able to take the compression change created by 1/32 less combustion chamber. With 9/32 if the valves didn't hit, I doubt the bottom end would take the extra strain very long.

It’s a flat faced head combustion chamber is in the piston. Need to adjust the tappets as discoverer 🤦🏼*♂️

[T P]

If it does it again_ I'd recommend pulling the radiator out and having it flow tested by someone competent. If there is insufficient flow top to bottom this can result in pressure being generated at the top and a slight vacuum at the bottom. Said vacuum can result in air getting sucked in around the water pump seal which is only intended to keep pressurised water in not air out of a vacuum. Once air gets in it gets dissolved in the water but eventually makes it's way out the cap taking some coolant with it. It's not a common scenario but I have seen it a few times when the radiator down tubes are partly blocked. Modern radiators are a bit miserable in their specs and don't have the generous capacities and dimensions of the old days very little crud causes a drastic deterioration in performance. I once saw a tractor suck in the bottom hose when the thermostat opened because someone has sealed a small leak in the radiator with egg white and blocked a load of down tubes, it too was pumping the water out into the expansion tank but not overheating. Bear in mind that a perkins engine with the timing gear driven water pump will suck crankcase gas into the system if this happens and that can give a false indication on the gas test indicating a faulty head gasket when it is not. If it were me the next stop is the radiator core testing for through flow in case someone's been sealing leaks with the old wonderweld or radweld etc and the downtubes in the core are partly blocked and unable to take the full flow from the water pump.

[ACE]

If it does it again_ I'd recommend pulling the radiator out and having it flow tested by someone competent. If there is insufficient flow top to bottom this can result in pressure being generated at the top and a slight vacuum at the bottom. Said vacuum can result in air getting sucked in around the water pump seal which is only intended to keep pressurised water in not air out of a vacuum. Once air gets in it gets dissolved in the water but eventually makes it's way out the cap taking some coolant with it. It's not a common scenario but I have seen it a few times when the radiator down tubes are partly blocked. Modern radiators are a bit miserable in their specs and don't have the generous capacities and dimensions of the old days very little crud causes a drastic deterioration in performance. I once saw a tractor suck in the bottom hose when the thermostat opened because someone has sealed a small leak in the radiator with egg white and blocked a load of down tubes, it too was pumping the water out into the expansion tank but not overheating. Bear in mind that a perkins engine with the timing gear driven water pump will suck crankcase gas into the system if this happens and that can give a false indication on the gas test indicating a faulty head gasket when it is not. If it were me the next stop is the radiator core testing for through flow in case someone's been sealing leaks with the old wonderweld or radweld etc and the downtubes in the core are partly blocked and unable to take the full flow from the water pump.

Second above. Rad is generally the cause of most head gasket issues one way or another.
Spend several hours cleaning rads some times and still not get them 100% clean.

[eyetee]

If it does it again_ I'd recommend pulling the radiator out and having it flow tested by someone competent. If there is insufficient flow top to bottom this can result in pressure being generated at the top and a slight vacuum at the bottom. Said vacuum can result in air getting sucked in around the water pump seal which is only intended to keep pressurised water in not air out of a vacuum. Once air gets in it gets dissolved in the water but eventually makes it's way out the cap taking some coolant with it. It's not a common scenario but I have seen it a few times when the radiator down tubes are partly blocked. Modern radiators are a bit miserable in their specs and don't have the generous capacities and dimensions of the old days very little crud causes a drastic deterioration in performance. I once saw a tractor suck in the bottom hose when the thermostat opened because someone has sealed a small leak in the radiator with egg white and blocked a load of down tubes, it too was pumping the water out into the expansion tank but not overheating. Bear in mind that a perkins engine with the timing gear driven water pump will suck crankcase gas into the system if this happens and that can give a false indication on the gas test indicating a faulty head gasket when it is not. If it were me the next stop is the radiator core testing for through flow in case someone's been sealing leaks with the old wonderweld or radweld etc and the downtubes in the core are partly blocked and unable to take the full flow from the water pump.

Thanks folks I'll be keeping it under scrutiny and the first sign it's pressurising I'll get the rad looked tested.

[ACE]

Thanks folks I'll be keeping it under scrutiny and the first sign it's pressurising I'll get the rad looked tested.

Be too late then damage already be done. Golden rule Fix the cause not just the fault.

[ACE]

You should check transmission cooler too cause if thats blocked it will stop coolent flow too.

[eyetee]

Be too late then damage already be done. Golden rule Fix the cause not just the fault.

Understood, when I had it apart last year I fully flushed the rad, the engine thank fully never overheated or showed signs of overheating.

[eyetee]

You should check transmission cooler too cause if thats blocked it will stop coolent flow too.

Is that the alli tube structure with water going through the center and oil in separate tube cavity?
If it is we had this out and tested for flow and leaks. Water and oil werent mixing anywhere.