15 replies to this topic

[mini-mad-mark]

Trying to start my rebuilt engine and there was an oil leak between the block and the front plate, at the front of the engine (A+  leak is where the block "curves" inwards if that makes sense - adjacent to the chain tensioner?)

 

No problem I thought, stripped down, fitted new gasket and it still leaks.

 

Any thoughts as to what might be wrong/what I might be doing wrong?

Edited by mini-mad-mark, 27 November 2024 - 12:07 AM.

[Spider]

Perhaps a leak through the Main Gallery Oil Plug ? That's just there in the front, under the water pump, behind the Alternator.

[bpirie1000]

Any pics may assist?

Is oil level correct? What grade oil are you using?

[mini-mad-mark]

I did try to get a picture (to send to the original builder.....) but its a black painted block and clean oil so really hard to capture.

 

Attached is a "library" picture, as they say, indicating where the oil is coming from (well hopefully - I'm still a novice at doing the picture thing!)

 

 

 

I'm pretty sure it's not coming from the oil gallery plug as it only emanates from the block about halfway along the curved section (if it came from the plug it would be all the way down the join of the plate to block?)

 

Classic 20/50 oil filled to just below Max on dipstick

 

Engine is out of the car now as I have some other unrelated problems which I found trying to start it (intermittent oil pressure and I think incorrect ring gear now I've removed the starter)

 

Going to strip the engine down and try to see what's going on with all these things

 

Just wondered if there was anything I might be missing during the reassembly of the front plate (was a decent quality gasket with Blue Hylomar sealant applied) - I managed to get the timing chain cover on without that leaking so I think I'm reasonably competent but it has got me stumped a bit.

 

 

[Spider]

Yeah, now I see this I'm also inclined to say it's likely not the gallery plug.

There's no other pressurised oil around that area.

 

I'd be fairly sure it's just the front engine plate gasket, but while it's apart, I'd suggest checking the block for scores or poor factory machining (I've had a few A+ Blocks that needed to be re-faced on that end) and also that the plate itself is flat and unmarked.

[bpirie1000]

Seams a strange one but at least the engine is out. Count it be dripping down from a rocker cover leak?

[mini-mad-mark]

Seams a strange one but at least the engine is out. Count it be dripping down from a rocker cover leak?

No, definitely coming from the plate in the area indicated - as mentioned now I have the engine out I'll be able to get a better look and easier access to re-assemble (hopefully doing a better job then the engine builder and myself the first time!)

[mini-mad-mark]

Perhaps a leak through the Main Gallery Oil Plug ? That's just there in the front, under the water pump, behind the Alternator.

 

Now I have got the engine out I can now see that it IS coming from the gallery plug - you were spot on so the front plate will have to come off again! 

 

 

However I now have a second and more serious issue.

 

I have intermittent oil pressure - I didn't notice the first time I was cranking the engine over to get oil pressure (and starting it) as I found the leak and stopped 

 

It seems to take a longer time than I would expect to get oil pressure up, then it takes a while to lose the pressure which I would expect with a rebuilt engine.

I cranked it again 2 or 3 times first couple of times it got pressure immediately but then I went to do something, left it for 5 minutes then I came back, cranked for more than a minute and didn't get any pressure at all 

 

I'm going to try to fix the leak and then crank it over again to see whether it is still doing it but anybody got any thought on the cause of intermittent oil pressure (during cranking) 

 

Yes I have got the O ring between the box and engine!

 

Could fitting a centre oil pick up pipe cause this if done incorrectly - NB wasn't done by me but I had this done before I assembled the engine/box so I know it was done recently?

 

 

I did start the engine after the first cranking session - I expected it to take a while to make oil pressure the first time but it did make pressure and then it ran with  OK pressure (60psi at 2000rpm) but then I had the leak issue and stopped and since then I've had this oil pressure fluctuation/intermittent issue. its also a bit lower pressure than I would like on cranking (about 30psi)

[nicklouse]

Checked the pressure relief valve. 

[Spider]

As Nick suggests check the Relief Valve first, but I'm a bit suspicious that you could have leak back through the pump.

 

That could be a gasket sealing issue (bolts being too long is a common cause) or the clearances in the pump being too big.

[mini-mad-mark]

Cheers both. PRV is all good, I suspect the oil pump gasket/fitment too. But seeing as I have to strip the engine now to get yhe oil gallery plug out (unless there is some way to do it I haven't found believe me I've tried) as removing it will introduce swarf one way or another, then it will mean looking at the oil pump any way and/or replacing it so I'll soon know.

[coopertaz]

 

Seams a strange one but at least the engine is out. Count it be dripping down from a rocker cover leak?

No, definitely coming from the plate in the area indicated - as mentioned now I have the engine out I'll be able to get a better look and easier access to re-assemble (hopefully doing a better job then the engine builder and myself the first time!)

 

would shy away from calling anyone who built this engine with so many issues an engine builder!!

[mini-mad-mark]

Now I have found an even more serious issue (yes it is getting worse the more I look) but which is almost certainly someway related to the intermittent oil pressure so should address that (eventually!)

 

Drained the oil ready to get the transfer gear housing off to look at the oil pump/gasket and the oil is full of ground up dust/dirt - doesn't stick to the sump plug so not steel - bearing or pump? PRobabl;y happened the first time I turned the engine over and started it I assume.

 

Looks like something is majorly knackered but I can't get the flywheel off atm with my crappy little puller so waiting to borrow a "gerroff ya b@stard"  - I'll report back after the holidays if I can diagnose the issue - I'm hoping to find something obvious.

 

Thinking it maybe something I've done when fitting the short motor to the box - I did triple check the primary and idler gear clearances and I believe they were correct so I hope its not my error but we'll see

 

Edited by mini-mad-mark, 19 December 2024 - 10:38 PM.

[mini-mad-mark]

Had a bit of a (fed up with this sh!t) break from working on the engine over Christmas (and also to enjoy some family time!!!) but got motivated again and back onto it this week.

 

 

Removed flywheel and transfer gear housing and removed and had a quick look inside the oil pump, looked OK, no scoring so I didn't think the (non-magnetic) debris in the oil was pump body, however what I didn't notice immediately.....

 

The oil pump gasket was fitted with the holes transposed i.e. the small hole over the big port in the block/pump and vice versa. Obviously not correct - but would this be enough cause an oil pressure issue?

 

 

Removed the big ends and mains caps, All four big end bearings are scored, more heavily on 2 & 3, the journals are scored on 2 & 3 but not on 1 & 4, centre main bearing slightly scored, no scoring on any of the mains journals

 

(No scoring on cam bearings, journals or lobes, cam followers OK)

 

 

I guess this happened at the point I started the engine, whilst I was watching the engine and not the oil pressure gauge which I assume at some point went down or maybe even to zero (based on my second attempt to crank the engine after trying to fix the original leak (unsuccessfully as per above comments) - and before anyone askes yes I did build up the oil pressure with the plugs out before I started it (for the only time) which didn't appear to take an overly long time to build up to 50psi on the starter.

 

Obviously there is a thin layer of sludge in the bottom of the gearbox.

Edited by mini-mad-mark, 17 January 2025 - 05:55 PM.

[imack]

My experience from years ago of fitting the oil pump gasket back to front (as you've done) on a new engine resulted in zero oil pressure. As a result, I now always fit the gasket to the block then fit the pump, rather than fit the gasket to the pump first.