DaveRover3500s
Member
Hi all. I posted this on end of an older thread for tappet noise but in hindsight thought it is better to start a new thread as it’s separate problem.
Having noticed blue smoke in rear mirror on occasion which has got more noticeable since mid part last year. The engine was rebuilt with newly overhauled Vitesse heads in sept 22- the vitesse heads done in oct 21. So yesterday I finally got round to doing a compression test. The highest was 165psi and lowest 155. I believe that variation is within tolerance? The spark plug condition upon examination was telling. 7 of the 8 were pretty much text book- brownish and dry - as you would expect to find them- except for cylinder position No.6. This plug was oily as per pic and sooted up. Clearly oil is entering the cylinder. When driving blue smoke is noticeable when coasting down hills and on accelerating from traffic light/standing after idling a while.
My thoughts are valve stem seal issue- compression is good at 155psi (11bars) and no oil is being pumped out any seals engine is very oil tight. Tad miffed as these heads were fully overhauled prior to fitment in Oct21- or so I was told…..
Any advice on likely chance of it being valve steam seal? Assume inlet one? (But would do both). I have read up on how to replace with head in situ via the rope into cylinder ‘trick’ to stop valve slipping down into cylinder when using a little spring compressor tool to release collets which I am happy to do. I was going to wait till post summer but tempted to do and just see if it solves it. Why would one seal go?
I still have tappet noise issue but that can wait till winter (is my thoughts on that). That’s on the other bank and is either No1, no 3 or no 5 cylinder. No.1 compression was 155psi and no 3 and 5165 psi. It’s not seriously noisy tappet and only appears noisy once warmed up- it’s ok when cold from start once oil gets round.
Having noticed blue smoke in rear mirror on occasion which has got more noticeable since mid part last year. The engine was rebuilt with newly overhauled Vitesse heads in sept 22- the vitesse heads done in oct 21. So yesterday I finally got round to doing a compression test. The highest was 165psi and lowest 155. I believe that variation is within tolerance? The spark plug condition upon examination was telling. 7 of the 8 were pretty much text book- brownish and dry - as you would expect to find them- except for cylinder position No.6. This plug was oily as per pic and sooted up. Clearly oil is entering the cylinder. When driving blue smoke is noticeable when coasting down hills and on accelerating from traffic light/standing after idling a while.
My thoughts are valve stem seal issue- compression is good at 155psi (11bars) and no oil is being pumped out any seals engine is very oil tight. Tad miffed as these heads were fully overhauled prior to fitment in Oct21- or so I was told…..
Any advice on likely chance of it being valve steam seal? Assume inlet one? (But would do both). I have read up on how to replace with head in situ via the rope into cylinder ‘trick’ to stop valve slipping down into cylinder when using a little spring compressor tool to release collets which I am happy to do. I was going to wait till post summer but tempted to do and just see if it solves it. Why would one seal go?
I still have tappet noise issue but that can wait till winter (is my thoughts on that). That’s on the other bank and is either No1, no 3 or no 5 cylinder. No.1 compression was 155psi and no 3 and 5165 psi. It’s not seriously noisy tappet and only appears noisy once warmed up- it’s ok when cold from start once oil gets round.
