V8 Tappets and oil

Managed to pick up the RRC that I got on eBay for £350 today.

Now bearing in mind I only wanted it for the gearbox (auto with the BW transfer box with viscous coupling) for burrt, the fact it had a 3.9 efi was by the by.

Started it up at the bloke's house, where it hadn't moved since May, and the tappets were a bit noisy, but soon quietened down. Normal for a V8 that has stood for a while, as the oil has drained from the top of the engine. It drove home well enough, although the shocks are shagged, and some of the suspension bushes are best described as "worn".

Anyway, get home today, and notice the oil light is flickering when in idling gear (1,2,3, D or R) but extinguished when idling in P or N...... When driving, no oil light...... Tappets a little bit rattley.

Had checked all levels before we left and was satisfied all levels ok, in fact new oil was in the engine.

Left the engine to cool down for a couple of hours. Rechecked the levels, still bang on where it was when I picked it up. Restarted it, shifted through the gears with it stood still, no oil light

Found an oil container under the seat for......10w40 fully synthetic oil......

I thought the oil didn't seem quite right, and was a touch thin. There is no other noise when cold other than the tappets, ie no grumble from the mains or big ends.

Gonna drop the oil tomorrow and replace it with some nice old fashioned 20w50 and see if the same occurs, else I'm looking at a rebuild of the engine :-( Will probabably drop the sump pan too to check for sludging. After all, don't want to put a knackered enigne in to have to have to take it to rebuild later......

On a positive note,the gearbox seems good, and it also has what can be described as the best top and bottom tailgates I have seen on a RRC in a long long time.

-- To reply direct rot13 me

bURRt the 101 Camper

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200TDi Disco with rotten floor 200 TDi DIsco, "the offroader" 1976 S3 Lightweight
Reply to
Simon Isaacs
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I doubt very much that the change of grade would cause the light to flicker when hot on its own, most likely you'll find the mains down to copper on the lower half shells and the same on the upper halfs of the big-ends. That'll be where the pressure's pissing off to! It should, however, be running 20w50 if it's the old-style pump, and a thinner oil certainly won't be helping matters. Check also that it isn't drawing air at the oil pick-up to block gasket.

Billy bonus there, then.

Badger.

Reply to
Badger

Now. Does this mean that I can have dibs on the tail gate(s), and help you remove the engine/box, and fill the golf with bits to make mine more

- well better than it is at the moment!

Thats is you break it and dont end up getting rid of a disco!

:):)

Reply to
Mark Solesbury

what should the oil pressure on a hot 3.5 v8 be?

my 101 only has a gauge not a light. It drops down to zero (or very very close to it - perhaps 2 or 3psi) sometimes when hot and stationary. Comes back up when you get moving again.

Gets up to about 15psi or so when moving.

I bought a gauge that reads up to 80psi or something so it barely registers!

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The 101 Forward Control Club and Register

Reply to
Tom Woods

Tom Woods uttered summat worrerz funny about:

Reply to
Lee_D

Tom Woods uttered summat worrerz funny about:

Erm.... how to say this and be positive..... I may have some spare heads and also 15 valve guides (I only had one fitted) ... i'll bung them on the pile to go for your next rebuild ;-) It'll be part way to your project rebuild at least :-)

Lee

Reply to
Lee_D

It aint the heads, done them! Im thinking it will be what badger says. Ive not had the sump off yet. Probably shant bother if i can find another engine instead!

its wierd though as when the oil pressure drops down to bugger all when it is hot my dodgy lifter (the one that is on the round cam lobe) doesnt tick lounder like it usually does at startup.

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The 101 Forward Control Club and Register

Reply to
Tom Woods

Tom Woods uttered summat worrerz funny about:

I know the heads will be fine... I was just looking for a good excuse to bung them on the pile. :-)

Would you like them sir? I'm sure I've got them.. just need to find them SD1 ones apparently if it makes any difference?

Lee

Reply to
Lee_D

On or around Sun, 24 Jun 2007 23:52:53 +0100, Tom Woods enlightened us thusly:

30-40lb, engine hot at 2500 rpm.

although a bit less than that will not hurt it unduly if it's got good oil and filter.

it's not unusual for it to drop to very-low when idling and hot though. take a look at the specs for oil light switches, they switch at about 4psi or something for the early V8s.

Reply to
Austin Shackles

V8s don't have a whole lot of oil pressure (compared to a lot of modern engines). On my 1988 Vitesse spec V8 (rebuilt 20000 miles ago) the oil light flickers at 800rpm when hot. I am running 10-40 semi- synthetic, and it was designed for 20-50. According to Hardcastle's V8 tuning book they were designed for 35psi at 2400rpm, and I quote "The system is a high-volume system, not high-pressure". I don't think it is a problem - if I hear any knocking from the bottom end then I'll take it more seriously. Probably drop the sump and look at some of the big end shells. I would be curious to fit a pressure gauge though - maybe I should do that.

I suspect the pressure switches that operate the oil light are also a bit variable, but you have to be a bit careful when fiddling around the oil pump as it is not self-priming. I had a V8 in a 1974 P6 and was told that low oil pressure might be due to the pressure relief valve being scored and worn, and better pressure when running could be obtained by fitting a different spring (from the MG V8). This simple after lunch mod became a real pain when I found I had lost all oil pressure, which resulted in me having to strip the pump down and fill it with vaseline (the recommended way of making it prime OK).

These days I have a bit of copper pipe that allows me to connect an electric drill to the oil pump shaft after removing the distributor. That way I can always make sure the oil system is full before starting an engine after a rebuild or fiddling around with the pump.

Steve

Reply to
Cheshire Steve

30psi, plus or minus 5psi, engine hot, 2400rpm. Most brand new engines only muster about 30 on a good day, the ones that reach 35 are the exception!

Not good.

Reply to
Badger

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