Stuck rings? Help!

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rob1miles

Well-Known Member
Posts
3,565
Location
Slough and Bath
Hi, I run a Perkins 4203 in a 109. Engine blew a a few weeks ago and I got and fitted another one. Replacement looked good; clean oil and water and oil on "full". Its a pig to start and is blowing oil from every posible place. So much presure it blew the dip stick out and the filler cap off. Looked like a steam engine!

I've just driven it about 5 miles and it is now possible to drive but spews a pint or so every mile, is down on power and running hot, blowby is massive, you need to keep the windows open!. Cracked injectors at idle and each clylinder out slows the idle. No unusual presure in cooling system. Just pulled the injectors and 2 look fine and two were soaked in engine oil. I've put penetrating oil in the cylinders and redex in the fuel and cylinders and I'm going to leave it overnight. It got a lot better in the first 10 mins of running but now its not getting any better. I need ideas.

I don't want to pull the pistons if I can avoid it as this is a big job. I don't think its the head gasket but it could be into the tappet side. But I'm sure all cylinders are firing a bit at idle. Its not really drivable because it pushes oil out so fast it looses oil presure after couple of miles. I think the engine was standing 2 to 3 years and it looked like the injection was retarded. Thanks!
 
I don't think you are going to get away with anything other than head off and pistons out for a good examination of it. You say it's stuck rings - could be rusted bores if it's been stood that long... If it's loosing oil pressure too then that indicates serious problems I would have thought.
 
The oil pressure is becuase it blowing so much past the crank seal the level is going below the pick up. Once it stops pressurizing the case that wil fix itself. The engine is not corroded - the head looks newish and the rocker gear was clean and in good condition, tappets all fine and head torques OK. I could take the head off but getting the pistons out could be a big job. It took 6 hours to get the engine in and I'm in no mood to take it out, its 288kg and I have to work outside in the road. I was suprised by the gunk on the injectors when I swapped them and I wonder if its been run too slow and the pump was off by about 5deg (I've assumed retarded but need to confirm that). What's puzzingl me is that the oil was spot on upper line on did stick and there were no leaks, now it holds that level for 5 mins once its running, so I think it must be someting that happened while it was stood.
 
Hi, I run a Perkins 4203 in a 109. Engine blew a a few weeks ago and I got and fitted another one. Replacement looked good; clean oil and water and oil on "full". Its a pig to start and is blowing oil from every posible place. So much presure it blew the dip stick out and the filler cap off. Looked like a steam engine!

I've just driven it about 5 miles and it is now possible to drive but spews a pint or so every mile, is down on power and running hot, blowby is massive, you need to keep the windows open!. Cracked injectors at idle and each clylinder out slows the idle. No unusual presure in cooling system. Just pulled the injectors and 2 look fine and two were soaked in engine oil. I've put penetrating oil in the cylinders and redex in the fuel and cylinders and I'm going to leave it overnight. It got a lot better in the first 10 mins of running but now its not getting any better. I need ideas.

I don't want to pull the pistons if I can avoid it as this is a big job. I don't think its the head gasket but it could be into the tappet side. But I'm sure all cylinders are firing a bit at idle. Its not really drivable because it pushes oil out so fast it looses oil presure after couple of miles. I think the engine was standing 2 to 3 years and it looked like the injection was retarded. Thanks!
its definitely blowing and pressurising the crank case, rings or head gasket or any other its going to need pulling apart to fix
 
A compression test will tell you a lot and you really ought to run one before you go taking the engine to bits. You need to be able to pin-point the problem before you yank the head but it does look like you will be stripping it down, come what may.
 
A compression test will tell you a lot and you really ought to run one before you go taking the engine to bits. You need to be able to pin-point the problem before you yank the head but it does look like you will be stripping it down, come what may.
X2

I agree that a compression test could help - I'd prefer a leak down test however...

...anyway the thing to remember is - if you were coughing up blood - would you go to see a doctor or just go to bed early with an asprin?

The chances of having to strip things down seem high.

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The only other thing that comes to mind - this essentially being a tractor engine - is => correct weight oil? (Modern thin stuff will probably not be what the designers envisaged)
 
a compression test will only tell you what you know already, its blowing in to crank case
Oh yeah I agree that it sounds like it is blowing from below but there is more than one cylinder - it might be useful to know if they are all as bad as each other.

It could as you say mean everything needs to be stripped down and visual inspection shows up obvious trouble (making a test pointless) - but - we've got an OP who says he doesn't want to do that...

...he might not have that choice or luxury in the end but if he wants to spend some time checking before pulling - then...
 
What's putting me off pulling the head is that I don't think its a head gasket. If it is the gasket they are only £19 and its a simple but heavy job. If its the rings I need the pistons out and I'm not sure they come out the top. If the engine was ok when it was stored, its a big "if" but everything esle about the engine seems good, then time spent freeing the rings in situe saves a lot of time, cost and possible damage in the strip down. There's nothing I can do to free the rings with the head off I can't do with it on. I'm looking at some chemicals such as 1,2-Dichlorobenzene which dissolves carbon, I can put some down the injector holes and turn the engine a few times and leave it for a day or two.
 
It's probably the very reason it was taken out and stored, its "****ed" ! Pistons will come out the top, but it will probably need new liners, which are pressed in and new rings at the very least, you mention it was better after you first put redex in the bores, this confirms state of innards..
 
Yes I've had a look at the manual now, its got 3 compression rings and 2 oil control and as you say, they come out the top ok. Its odd because the engine I took out ran fine until the head gasket went (again) but was completely clapped out; cracked liners, top land missing, rockers worn to bits, almost no oil pressure but started on the button and pulled strongly. All the parts I've seen on the "new" engine are showing a lot less wear and its much quieter and smoother, it was pulled out of a SWB for a TDI. It had a fuel starvation problem but i found the feed and return lines reversed on the filter so it was getting unfiltered fuel and the injector pump was full of muck.
 
What's putting me off pulling the head is that I don't think its a head gasket. If it is the gasket they are only £19 and its a simple but heavy job. If its the rings I need the pistons out and I'm not sure they come out the top. If the engine was ok when it was stored, its a big "if" but everything esle about the engine seems good, then time spent freeing the rings in situe saves a lot of time, cost and possible damage in the strip down. There's nothing I can do to free the rings with the head off I can't do with it on. I'm looking at some chemicals such as 1,2-Dichlorobenzene which dissolves carbon, I can put some down the injector holes and turn the engine a few times and leave it for a day or two.

No one thinks it's head gasket. If it's pressurising the case that fast that the breather cannot cope then the rings are well stuck. You wont fix them without having the pistons out, no matter how much you understandably wish it were possible.
 
regardless of how inconvenient it is for you, it wont fix itself.

compression testers for diesel engines are quite specialist and expensive (due to compression ratio) i don't even think that's worth bothering with
 
Diesel compression testers used to be very expensive indeed but now you can buy a kit for £20 - £30 on Amazon, same goes for leak-down testers. Perfectly adequate for occasional use.
 
Thanks, just had a look, pleasantly suprised. This could help as I could soak and motor the engine for a while and see if the pressure comes up before starting it again. I need to avoid more mess on the road! (I've already jetwashed and scrubbed the road it still looks awful). I need to find a kit with the right adaptor for the old style CAV injectors with the 2 stud fixing. There's an intersting UK / US split on stuck rings. The UK approach seems to favour a strip down, the US one is all about soaking free as do the farmers. This problem seems common on old tractors as they stand a lot more. I'ver ordered some "Marvel Myster Oil" (I kid not) that comes highly recommended in the US. It may be snake oil but if its snake oil that frees rings I'll be happy for £12.
 
Marvel mystery oil does appear to help smoky old engines - loads of videos on yew toob - but what you've described is on a different level. Coughing up blood and emptying the crankcase - very different level (sounding like Donald Trump!)

If you've never had a go at removing caked on carbon from piston grooves (obviously with pistons out of an engine) then I can understand why you are chasing these types of solutions...

...having had a go with screwdrivers and other things I shouldn't have used (!) there's no way I can see how a chemical added to the engine oil is going to help something that is seriously stuck. Removing a piston and soaking it in something for a few weeks - yeah perhaps - as an additive... hmmm... sorry I'm not so positive about those chances coming good. Still I'll be happy to hear I'm wrong (!)

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I'll mention it again just in case - what weight engine oil are you using - is it what Perkins say should be used?

(In the situation where the oil weight is incorrect I wouldn't expect great changes but it might be good enough to keep you going for a while)
 
The rings on my PT were stuck. I managed to free a couple of them off with the piston out - engine was getting a full stripdown anyway - but even carefully poking and prying with thin things I still managed to break two of them before I gave up. Rings are quite expensive for it in comparison to what you said the perkins rings were (might have been on LRUK) so assuming you end up going down the stripdown route I'd have a spare set sitting ready anyway and probably just change them regardless of condition.
 
The guys who have had sucess with soaking say it can take several weeks and I have the time so its worth a go. I have freed rings on strip downs in the past (not on a Perkins) and in one case I'd used redex for a while and the carbon was much softer so I've not lost all hope. The parts cost is very good, probably about £60 rings and gaskets, the head looks nearly new and oil pressure is OK so its a case of head of, sump off, split the big ends and lift the pistons. All Perkins are std bore so its easy to order the rings in advance. What's holding me back is having to do it in the road, if I could get it into a garage I think I'd just strip it as everyting is oiled and looks like it will undo easily. The other problem is lifting the head, its very heavy. Last time I put a rope over my shoulders and stood on a plank across the wings. Osteopath bill is likely to larger than the parts bill!
 
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