Rutty Posted August 20, 2021 Share Posted August 20, 2021 What are peoples thoughts on what is wrong. It also smokes from the dipstick. 20210820_163945.mp4 Quote Link to comment Share on other sites More sharing options...
yorkshire_spam Posted August 20, 2021 Share Posted August 20, 2021 Looks a bit "breathey"... maybe test the compression? Maybe 1 or more pistons needing rings? Quote Link to comment Share on other sites More sharing options...
Hogie Posted August 20, 2021 Share Posted August 20, 2021 serious blow by. As above check compression pressure etc. Check all the pipes in the breathing system - they may be blocked. Roger Quote Link to comment Share on other sites More sharing options...
Callan Hyde Posted August 20, 2021 Share Posted August 20, 2021 Excessive blow by, going off the amount i would suggest that it needs rings on more than 1 cylinder 😟 Quote Link to comment Share on other sites More sharing options...
RobPearce Posted August 20, 2021 Share Posted August 20, 2021 Yep, I agree with the three gentlemen above, that looks like failed rings on a couple of cylinders. Quote Link to comment Share on other sites More sharing options...
Rutty Posted August 20, 2021 Author Share Posted August 20, 2021 If it is just failed rings would I get away with just fitting new rings or would I be looking at a re-bore, new pistons etc? Quote Link to comment Share on other sites More sharing options...
yorkshire_spam Posted August 20, 2021 Share Posted August 20, 2021 If it really is just rings and there's no ovality, serious wear or damage to the cylinder bores a hone and new rings should sort it. Quote Link to comment Share on other sites More sharing options...
glang Posted August 20, 2021 Share Posted August 20, 2021 Being realistic if the rings have worn that much then the bores will have the same amount of wear and a rebore is needed. If you put new rings in worn bores their sealing maybe even worse. A compression check, as said above, is essential. Do it once 'dry' and once with a small amount of oil poured into each bore via the sparkplug hole then compare the two readings to positively identify ring blowby.... Quote Link to comment Share on other sites More sharing options...
Rutty Posted August 20, 2021 Author Share Posted August 20, 2021 Thanks for you comments its as I thought. I am picking a compression tester up on Monday so there is not a lot I can do till then. Final question its a Mk1 2.5 Pi on SU's I know I can take the head off in situ but can I drop the sump and remove the pistons or is it the block out job. Thanks Mark Quote Link to comment Share on other sites More sharing options...
glang Posted August 20, 2021 Share Posted August 20, 2021 How many miles do you think the engine has done? How does it run with the breather system all connected correctly? Id be surprised if you cant take the pistons out in situ although it wont be a pleasant job and also difficult to maintain the required level of cleanliness... Quote Link to comment Share on other sites More sharing options...
thescrapman Posted August 20, 2021 Share Posted August 20, 2021 Might be just sticky rings, hasn't run much for many years has it? I have a few engines that breathe like that, have all had a go in my PI, they'd didn't before I fitted them, but did after a few years of being driven by me (or Chris) Quote Link to comment Share on other sites More sharing options...
Rutty Posted August 20, 2021 Author Share Posted August 20, 2021 I don't know how many miles the engine has done but there is no top or bottom end noises that I can hear so it would suggest its not excessive. It has been suggested it could be sticky rings due to lack of use over the last 10 years and I was told to put some diesel in the bores to see if it releases them. I will give that a try once I have done the compression tests. Thanks for you comments Mark Quote Link to comment Share on other sites More sharing options...
Nick Jones Posted August 20, 2021 Share Posted August 20, 2021 What is the oil like? If it’s got lots of petrol and or water in it you can get a fair bit of gassing off as it warms up. Looking at the pulsing though, I’d say two or three cylinders with stuck/ broken rings. If it’s just been woken from long slumber then a good soaking with ATF, or even a bit of ATF in the oil might help free the rings off. Getting it properly hot and putting some load on it might also help. Not to depress you too much, I had similar with my old PI (didn’t chuff quite as much as yours) and messed around for ages trying free the rings and improve the breather system to minimal effect. It did drive ok, but used a lot of oil and blew oil out of every joint when pushed. Compression figures were uniformly excellent, I think because there was so much oil getting past the rings, every test was a wet test. In the end it got stripped and turned out to be quite clean inside (the ATF!) with all rings free and intact. The problem was that the bores had been quite rusty (could still see the witness marks where the rings had sat after 2k miles of running) and two of them were quite pitted high up. The vendor swore it hadn’t been “cracked off” Yeah, right. Had to rebore it, but the rest of it was pretty good, could have been worse. Good luck Nick Quote Link to comment Share on other sites More sharing options...
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