Club 80-90 Forums

Hi,
had a search but struggling to find definitive info; I've got no compression on cylinder 1 and low on cylinder 2 (1.9 DG late WBX).
Seemed to happen during a 60mph run, water temp was fine, slight knocking rapidly getting worse, van limps but low power knocks and as if a cylinder down (which it is).
Wet compression test raised compression so assuming bores/rings, worried about it being low on cylinder 2 but we'll see when we get it open.
Looking to get local engine reconditioner to install barrel and piston set which I will supply along with full gasket kit with black and yellow sealant etc.
They are happy to do it and have done work for me in the past but on more conventional engines and they are not flat four or WBX experts by any means; is there anything else that needs doing or anything that needs replacing when heads off and barrels & pistons replaced?
Anything that i can pass on would be appreciated.

Thanks, Chris.

There is no definative answer. Every single rebuild throws out different issues.

Main concerns;
Head stud are best released by manual tools and not by a gun ho attack using a rattle gun. You need to feel if the studs are releasing instead of twisting. Break a stud and tears will flow.

Cleanliness is paramount. And using the correct sealant around the cylinder head and on the head nuts. Also the piston sleeves' top and bottom seals need to sit in ultra clean grooves.

Is this an engine out procedure or engine in situ job, btw? If engine out, then replace the water jacket seal on other side, too.
Exhaust studs are in good condition, l take it? Replace if crusty.

what's the history of the van ?
is there oil in coolant or coolant in oil ?
have you done a sniff test ?
Has the garage checked preload on valves and the valve train on the left side ?

maxstu wrote: ↑28 Jun 2024, 16:40 There is no definative answer. Every single rebuild throws out different issues.

Main concerns;
Head stud are best released by manual tools and not by a gun ho attack using a rattle gun. You need to feel if the studs are releasing instead of twisting. Break a stud and tears will flow.

Cleanliness is paramount. And using the correct sealant around the cylinder head and on the head nuts. Also the piston sleeves' top and bottom seals need to sit in ultra clean grooves.

Is this an engine out procedure or engine in situ job, btw? If engine out, then replace the water jacket seal on other side, too.
Exhaust studs are in good condition, l take it? Replace if crusty.

Thanks, I think I'm going to go for it myself rather than giving it to an Engineering house.
I have about six weeks to get it sorted before a 5 hour drive and a week in Cornwall and can take my time and more importantly take extra care with it. I'm not an engine building guy but have stripped and rebuilt stuff in the past and I have Engineering background.
Will get a good quality gasket kit with correct yellow and black sealants.
Engine will be out (will be removed by my friend/mechanic who has stopped doing engine rebuilds annoyingly).
One exhaust stud is missing, assumed snapped, will replace and replace any others that look dodgy (or maybe all, I have a full set of new).
Thanks,
Chris.

Aidan wrote: ↑28 Jun 2024, 18:00 what's the history of the van ?
is there oil in coolant or coolant in oil ?
have you done a sniff test ?
Has the garage checked preload on valves and the valve train on the left side ?

Hi Aidan,
I have owned the van a couple of months, I've been running it fairly hard to see what breaks before a Cornwall trip in August.
I had some issues with oil light flickering and then on and off but oil pressure seemed fine when tested with a gauge (hot/cold & low/hi revs).
Both oil pressure switches replaced with correct ones, hi pressure switch was disconnected and earthed..
I don't think the PCB/buzzer assembly in the dash is working correctly; I've never had a buzzer despite having flickering / flashing oil light at over 2000RPM whilst driving with the hi pressure switch earthed..
Annoyingly whilst I was getting on top of and fault finding / fixing that (new Mahle oil filter, new oil relief valve spring, Mansispeed O-ring pump ready to fit, remote LP oil switch installed with T-piece for sender, VDO sender installed and ready for cable to VDO gauge on dash), it started running rough whilst on a 65mph run. Limped home with low power and no compression in cylinder 1 (nearside rear) and low compression in cylinder 2 (nearside front). Two offside are fine.
Both in one bank being down/low to me would indicate head gasket or something in common but wet compression test with oil in cylinder 1 immediately raised the compression which usually points to piston/rings/bore (but in a vertical engine..).

So plan is head off and see what I find; my thought is if I've got head off I may as well do barrels and pistons whilst I'm in there (and I'll do both sides obviously) and water pump. fit Mansispeed oil pump etc.
No coolant in oil or oil in coolant as far as I (or my mechanic) can see.
Unsure what sniff test refers to.
Have not had rocker covers off yet, could check valve gear before dropping engine.
Engine is still in van and runs (badly), will be coming out later this week.

Thanks,
Chris

You mentioned knocking that rapidly got worse, then flickering oil light.
My money would be on a failed big end bearing, usually #3, sometimes #1

PS cylinder numbering: #1 is RH nearest starter, #2 Rh rearmost, #3 is LH by clutch slave, #4 is nearest water pump.

Good luck.

.

Shouldn't that be lgbtq not trans?