Mysterious SBC Oil leak

[Nabbott]

So Pete (the engine builder) is going to send me a fitting that should do the business. He did also suggest another source for the oil leaks - it could be coming from the oil inspection galleries. Behind the gearbox adaptor....... Either way, the main seal would be the correct 1st fix and we'll see how we go from here on in.

Fingers crossed!

[Nabbott]

MarkWebb said:

hmm, as I said on 1st Jan

I know, I know - looks like you may have been 'on the money' - I just didn't want to believe it

Have decided that I may as well whip the box, clutch and flywheel off (he says casually like it's a trivial amount of spannering) at the same time. At least this way I can guarantee it gets sorted for the spring once and for all!!!!

[Nabbott]

Steve_D said:

There are 2 types of Torx bits....Torx and Torx-Plus so that may be the difference.

It may also be a Tripple-Square which is more like a spline.

Steve

Congrats - it's a Torx Plus! You learn something new EVERY day playing with these cars ... torx plus - who knew?....

[Nabbott]

If Thor did metal work (beyond knocking out the occasional heavy hammer), I think this is the kind of big end engineering he'd be doing.

6 bolts - and look at the size of that thing!

[Nabbott]

Well I may as well (but hadn't given it much thought to be honest!)

[Nabbott]

So bet you all thought I'd fixed this and forgotten to update you all??

NO - I've been buying a new house and spending WAY too much time on DIY since January to get the car back together. However tonight I finished whipping the gearbox, clutch, flywheel and adaptor plate assembly off to check the oil gallery and cam shaft plugs:




Now I don't know about anyone else but I have to conclude that there's no enough coming out of here to account for the vast leaks i was experiencing. The back of the adaptor plate was 'slightly oily' but nothing like what I was expecting had one of the plugs sprang a leak.

So unless anyone here has any better ideas I'm going to suggest that the rear crank oil seal was the culprit (and I could have been driving the car through this lovely weather over the last 2 weeks)

[Nabbott]

Paul,

Logically I think it can only have been the rear rank oil seal. There aren't any places left for it to leak from (and its 100% engine oil not gearbox). The definitive test would have been to have driven the car having fitted the new crank seal but given it was December (and the only other place it could have been was these plugs) I decided to make 100% sure and tear it all to pieces.

If it leaks on the next drive I think I'll be making an insurance claim for total loss from a mysterious fire (e.g. Me setting light to the bloody thing 😄)

[Nabbott]

Thanks Paul (so do I!). I checked the pipes pretty carefully there aren't that many even with the dry sump. Fingers crossed it's sorted this time around 😜

[Nabbott]

So the oil tank does have a breather but it's just vented to the open air (no catch tank). It could be loosing a bit from their but not anywhere as much as I was seeing

[Nabbott]

Right so I'm throwing in the towel on this oil leak - family, work and the fact that we're between 2 houses are conspiring against me.

Gentlemen - what I need now Is a trusted garage who know their way around a SBC that I can take the car to and they can fix the issue. Can anyone recommend anywhere in the south east? I'm in ascot for reference.

[Nabbott]

I seem to remember good things being said about Charles Dunn - great recommendation. Thanks.

[Nabbott]

Mark - I have a horrible suspicion you're right! I hate to admit defeat but time, inspiration and patience have all run out on me. I don't normally take the 'give it to the man' route as I perceive it as a failure but 'needs must' it's currently leaking like a pig and driving me crackers 😭. Just hope that Mr Dunn (or similar) can fit me in.

[Nabbott]

Mark - thanks. A solid endorsement always helps my process - just hope he can fit me in!

[Nabbott]

Andrew - thanks for your super detailed post! I've spoken with Earl previously and agree his knowledge and kinslers after sales care is EXCELLENT. I think the idea of buying their filler plates is a great idea (I'll order some on Monday). Whilst I'm perfectly capable of doing to work my patience (but more importantly my time) has run out. Having removed the kinsler assembly it was oil tight - but a couple of hours on the dyno was enough to undo my work .

Regards the additional oil scavenge I think this would be ideal BUT as the car will predominantly running on the road the opportunity for extended full throttle applications is limited (to say the least).....

The guy I'm sending the car too knows his way around a SBC so this coupled with the kinsler 'fillera' should maximise my chances of curing the big leak..... I can live with the engine sweating a bit of oil - part of their charm???!?

[Nabbott]

Mark - I'd be interested to hear what it was!

[Nabbott]

gt5594 said:

do make a pair of alloy fillers in different thicknesses which look a bit like stretched "s" shapes and are made to the shape of their own manifold.

Spoke to the team at Kinsler and they no longer make these

[Nabbott]

[quote=MarkWebb]Three bond 1217H
http://www.threebond.co.uk/Products/ThreeBondSeala...

Thanks Mark - looks like 1207B, may be an even better bet "and works effectively for the joint surfaces that have a larger clearance." I'll pass the recommendation onto Charles Dunn - who'll hopefully be able to take the car in next week.

[Nabbott]

Update

So the car is now with Charles Dunn and the bad news arrived late yesterday ......

With the engine removed and a list of remedial/preventative jobs listed (valve stem oil seals, valve spring check etc., etc.,) a leak down test was conducted and two cylinders on the left hand bank were much lower than all the rest (either a s a result of overheating or bore wash (or both!)). Nothing for it but to fully strip the engine to ascertain whether this is a rebore OR can be remedied with a light hone and a set of rings.

This has forced me into a decision - this is a very highly specced race engine and is not really suitable for the road. Essentially I think I need to sell the engine (either in component form OR rebuilt) and put the proceeds towards an American Speed 'crate engine' in a lower state of tune and thus more durable. 640 bhp is nice BUT not if it's going to bankrupt me.

The other option would be to sell the car as a rolling chassis (£28k?), "just add engine" + the engine (again either in components or rebuilt), lick my wounds and give up.

So my question(s) to the group is a) does anyone know about the market for a SBC race engine (I'll try and contact Peter Knight to discuss with him today) and b) does anyone have a SBC kicking around they'd sell me - only interested in one that doesn't need any work?

Yours, dejected, frustrated, poor and in the dog house with the wife :smile:

Edited by Nabbott on Wednesday 1st July 08:17

[Nabbott]

Thanks Roj. Troue is we're in the process of moving (next few weeks) and I have a house (and garage!) to build as first priorities!

Gutted I won't be able to drive the car to the Silverstone Classic which was my target

[Nabbott]

Mark the issue is that the entire engine has been built for max BHP. Thus the heads, cam and fuel injection are all spec'ed together. Just 'downing' the cam would mean the engine was Massively over throttled and the heads would be 'wrong' - resulting in a poor tuning motor. I spoke with Peter Knight at length yesterday. His advice was to strip it, rectify the two bad cylinders and then sell the engine as a 'kit' to be assembled by someone wanting a trick SBC race engine.

He's of the opinion that the assemblies are worth £6k 'all day long' - which would provide me with sufficient funds to buy a turn key engine from American Speed.....