M30 B34 low oil pressure - engine out!

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juzza
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M30 B34 low oil pressure - engine out!

Post by juzza »

Hi folks

Not been here for a while so apologies if I've missed this recently. My oil pressure light has been gradually taking longer to go out on initial start, sometimes up to 10 seconds. Accordingly I've not used it for a while & a trusted friend who owns a small engine shop wants to pull the motor. Ouch.

It may be just a clogged strainer but as it's 30 years old with 140k he wants to play it safe & have a thorough overhaul. Apparently there are cases of failed oil pumps / drives but I'm now asking for some advice, ie what to look for specifically, especially from those who've experienced this.

Additionally, what else to check / change while I'm there - engine mounts, oil seals, steering bracket strengthen etc etc.

Many thanks in advance...
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olympia57
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Re: M30 B34 low oil pressure - engine out!

Post by olympia57 »

I'd try another pressure switch first and also connect up a pressure gauge and actually check the true pressure .
The switch is situated on the head ,RHS at the rear so access is very good making it a quick and easy check.
Good luck.
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86_6series
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Re: M30 B34 low oil pressure - engine out!

Post by 86_6series »

+1 on the oil pressure check. Use a mechanical gauge, it could be the sending unit.
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Re: M30 B34 low oil pressure - engine out!

Post by baders »

+2 on checking the oil pressure with a gauge. Pretty simple to do. The oil pumps on the M30 are usually bullet proof, but the pressure relief valves have been known to stick partially open. Refurbishment is fairly inexpensive once you can get at the damn thing.
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Re: M30 B34 low oil pressure - engine out!

Post by Pod »

If it turns out that you do have poor oil pressure, rather than go to the expense of a full engine rebuild, why not just drop a replacement engine in? Much cheaper - and there's hardly a shortage of them out there!
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Re: M30 B34 low oil pressure - engine out!

Post by Brucey »

if the oil pressure switch seems mysteriously oily, the chances are excellent that it has simply failed. Note also that various other electrical idiosyncrasies can also lead to the oil pressure light staying on, often in combination with other dash lights.

cheers
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juzza
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Re: M30 B34 low oil pressure - engine out!

Post by juzza »

Thank-you so far chaps, very much appreciated.....
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Re: M30 B34 low oil pressure - engine out!

Post by bpoliakoff »

Two ways to look at this. If indeed it turns out to be low oil pressure, the fix depends on the intent of your future with the car. If not in the long picture I would say Pods suggestion is spot on. If the car will stay with you, an engine rebuild is in order as then you will know what you have, be able to trust it and be done with it. It may be no more than an oil pump, new bearings, rings, a valve job and seals. No heavy machining or pistons and may not be an exorbitant rebuild. One way or the other the engine will have to come out and you won't know which way to go until it's opened up. That will be when you can make a prudent decision.
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juzza
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Re: M30 B34 low oil pressure - engine out!

Post by juzza »

Holy toot, new pressure switch and the light goes out! Wasn't expecting that at all. Huge weight lifted here and many thanks for all the replies, cheers folks...
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Re: M30 B34 low oil pressure - engine out!

Post by Pod »

juzza wrote: Fri Nov 30, 2018 9:28 pm Holy toot, new pressure switch and the light goes out! Wasn't expecting that at all. Huge weight lifted here and many thanks for all the replies, cheers folks...
Yippee!
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