M30 B34 low oil pressure - engine out!
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M30 B34 low oil pressure - engine out!
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...
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...
1986 Zinnober 635 CSi
Re: M30 B34 low oil pressure - engine out!
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.
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.
1981 635 series 1
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Re: M30 B34 low oil pressure - engine out!
+1 on the oil pressure check. Use a mechanical gauge, it could be the sending unit.
86-635CSi
96-MB C220 SOLD
98-740i
71-Continental MK3
96-MB C220 SOLD
98-740i
71-Continental MK3
Re: M30 B34 low oil pressure - engine out!
+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.
1986 635csi LOCUTUS / Arktis Blau Metallic / Pearl Beige / S38B36/ Close ratio dogleg 5sp
2002 E46 M3 / Topaz Blau Metallic / Black Nappa / 6 speed SMG software tuned / Bilstein PSS10 Coilovers / CMP RACP reinforcement
2002 E46 M3 / Topaz Blau Metallic / Black Nappa / 6 speed SMG software tuned / Bilstein PSS10 Coilovers / CMP RACP reinforcement
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Re: M30 B34 low oil pressure - engine out!
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!
Re: M30 B34 low oil pressure - engine out!
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
cheers
~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Re: M30 B34 low oil pressure - engine out!
Thank-you so far chaps, very much appreciated.....
1986 Zinnober 635 CSi
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Re: M30 B34 low oil pressure - engine out!
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.
81 Euro 635 M90 with motronic. Currently under a complete nut and bolt restoration. Pictures at
flickr.com/photos/bertsphotos.
flickr.com/photos/bertsphotos.
Re: M30 B34 low oil pressure - engine out!
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...
1986 Zinnober 635 CSi