Serpentine Oil Pump Priming
Serpentine Oil Pump Priming
Author
Discussion

Griffit

Original Poster:

375 posts

236 months

Sunday 28th January 2007
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Yesterday was the big day - I picked up my Griff from the dealer and headed home for the first time, a journey of about 100 miles in the sunshine, hurrah! Anyhow, with all the excitement I probably covered about 130 gentle miles before I got home and tucked the car safely in the garage, ready and waiting to attend the Interpro rolling road day this morning.

Being a dilligent owner, before firing the car up this morning I decided to check the oil level, which to my horror was a little below the minimum mark on the dipstick yikes!! So off I went to Halfrauds to pick up 5 litres of Mobil 1 Motorsport to top up the engine, which ended up taking about 2.5 litres before closing in on the top line on the dipstick. Shortly after I was ready to start up and head out, but when I started the engine I noticed there was no oil pressure showing on the gauge and shut it off straight away. (About 10-20 seconds?) At this point I remembered reading the bit in the bible about priming the pump if the oil is allowed to run low....

Now I should point out that I kept an eye on the gauge frequently yesterday and the oil pressure was always fine, so I'm guessing the level had been higher and the pump had not got to the point where it had gone dry and stopped pumping. Obviously leaving the car overnight has let the oil run down into the sump, leaving me with a dry pump?

I decided that I would try the method stated in the bible, plugs out, fuse/relay for fuel pump removed, coil unplugged and see if that would solve the problem. I have spun the engine a couple of times but the gauge hasn't moved above the 0 mark, which I'm guessing means that I have failed so far? I haven't been able to try the oil-filter-off method yet as I was working alone.

Can anybody advise whether the gauge moves much if you are successful with this method? Does taking the filter off help that much? Alternatively can anybody help with what more I can do now? The bible doesn't cover much on removing the timing chain cover to get to the oil pump to pack it with vaseline on a serpentine engine.

At the moment I'm pretty much head-in-hands at the whole situation - this was not the start to my relationship with the car that I had envisaged cry

spend

12,581 posts

280 months

Sunday 28th January 2007
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You didnt mention all this earlier :-)

Is the oil pressure warning light going off when you crank the engine? It is possible your gauge is just faulty.

Dave

spend

12,581 posts

280 months

Sunday 28th January 2007
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I think he has gone to look :-))

350matt

3,896 posts

308 months

Sunday 28th January 2007
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With this complaint, the serpentine engines don't suffer anywhere near as much as the vee-belt
engines. In fact this the first I've heard of to do this.

I'd tempted to cehck the pressure with a mechanical gauge, especially if the oil light is going out on cranking

Matt

That Daddy

19,442 posts

250 months

Sunday 28th January 2007
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if your car as taken only 2.5 litres to full topping up,theres no way the pump as run dry i would go with spend on this and think your gauge maybe faulty,but you still need to know where that oil as gone,did the light go out(oil light)when it started.

spend

12,581 posts

280 months

Sunday 28th January 2007
quotequote all
350matt said:
With this complaint, the serpentine engines don't suffer anywhere near as much as the vee-belt
engines.


But you are still going to join the 430 club are'nt you?<BS>!

Dave

shpub

8,507 posts

301 months

Sunday 28th January 2007
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With a serp engine the oil pump is totally different and raerely needs priming as the design self primes usually. There is also little to go wrong with them as they are driven straight from the crank IIRC.

To prime them the engine needs to be turned over and it will take more than a couple of times to do it. Vaseline packing is very very much the last resort. Removing the oil filter is another trick - again covered in the bible.

The key point is the oil pressure light rather than the guage as the guage can be unreliable. If the oil light goes off. Everything is fine. Start her up and chcek for oil pressure. If it doesn't it might indiacte a problem such as a blocked or broken pick up or even a pressure spring gone.

mongoose

4,360 posts

284 months

Sunday 28th January 2007
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Are you giving it time enough for the gauge to come up?It is slow to react on a serp engine,so if your just spinning the engine,then instantly turning it off,it wont have had chance to react.

Griffit

Original Poster:

375 posts

236 months

Sunday 28th January 2007
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Thanks for all the replies guys, I hadn't gone to look (Dave), just decided to open a bottle of wine and forget about it for an hour or so! (And no, I hadn't mentioned the whole scenario with my post on fuel pump fuses/relays earlier as I was still in hope of being saved by the bible's methods!)

I can't recall whether the light went out when I started it, to be honest I saw no pressure on the gauge and killed it pronto! When I was cranking it earlier with the plugs out etc the light remained on for a bit, I'm sure it went off at some point but I thought it had gone out time-wise rather than due to pressure build up? I managed to loosen the oil filter but didn't remove it because I didn't have anyone to help.

Having checked the bottle it's taken about 3 litres now. The oil level wasn't so low that I needed a longer dipstick!

Mongoose / Steve - How long would I expect to crank for to see the gauge spring into life? Obviously there is very little load at present but I didn't spin for more than 10 secs max to save the starter etc

I've put the plugs back in loosely to stop anything entering the engine but am scared of starting it again in case there is no oil pressure.


Edited by Griffit on Sunday 28th January 19:51

Griffit

Original Poster:

375 posts

236 months

Sunday 28th January 2007
quotequote all
Just been reading something on the RPi website about pump priming, and then noticed the section below regarding overheating. (about half way down page) [url] www.v8engines.com/faq-gen.htm [/url].

I notice that one reason that your pump may not prime is because the pressure oil relief valve is stuck open in the pump body. I also see that overheating may cause this to happen.

As it happens the car did get quite hot yesterday when sitting in traffic in Gloucester, I was worried about sitting still, but the cooling fans could be heard operating which stopped me worrying too much, though I did turn off at one point.

Could this be something to do with the problem or does this only affect pre-serp cars? If this is a potential problem how difficult is it to check?

spend

12,581 posts

280 months

Sunday 28th January 2007
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Matey, stop worrying about, assume the gauge is barfed. Start again tomorrow & if the oil light goes out when you crank, get the plugs in and start it up. I think from the comments here its pretty solid we all reckon its just your gauge / sender ~ which may start working lazily. If there was no oil pressure you would have really thought it sounded like a bag of old bones when you fired it up earlier.

3 litres of wine in 2 hours was very impressive BTW (or did I read it wrong); God knows how much more you have had since then :-)

Just sleep easy, It'll be fine in the morning.

Dave

GreenV8S

31,017 posts

313 months

Sunday 28th January 2007
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Realistically you are unlikely to generate enough pressure just cranking the engine over to see it on the gauge. You may not even see the oil pressure warning light go out. For a serpentine engine it'll prime itself if you just start the engine, rev it to 2000 rpm and hold it for five seconds or so. If by then the oil pressure warning light is still on and the gauge is showing zero, switch off and be prepared for a lot of grief. It's not at all likely that you will damage the engine doing this, but the next step will be to strip down the pressure relief valve and if that isn't the problem then you have even worse trouble.

seasider

12,728 posts

278 months

Monday 29th January 2007
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I'm sure you've already looked but check the wire is on the sendor & tight

johno

8,593 posts

311 months

Monday 29th January 2007
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2 things ...

1 - My serp engine builds enough pressure on the starter to turn off the oil pressure light, just disconnect the HT lead to the coil. Then start the thing once the light is out. Run at 1500-2000rpm and watch the gauge. If it doesn't move after a minute or so then shutdown and investigate.

2 - I have previously driven my TVR with no oil pressure for about a 1000 miles. I knew the oil pressure gauge was buggered and couldn't get another one .. People are so bloody precious about oil pressure on here it is amazing ...

There are 2 systems on the car for oil pressure sensing, the gauge which is usually pretty inaccurate. Secondly the emergency last gasper which is on a seperate sensor, and the light comes on. This will occur around 5-7psi.

It seems that we become so preoccupied with oil pressure that we forget the engine was in perfect health and not showing any issues and suddenly the oil pressure drops of the earth it must be the engine that is buggered.

How many cars have we all got on our drives today that do not have an oil pressure gauge in them ? Loads I have no doubt .... Yet because we have a gauge we become absolutely driven by it in all circumstances.

I agree completely, that driving your engine without oil pressure will completely bugger it. But 99% of lost oil pressure, or wild fluctuations are caused by the gauge failing, not the engine in my experience, and I think if you flick through the forums it will prove much of this out.

I'll get of my soapbox now ...

johno

8,593 posts

311 months

Monday 29th January 2007
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Griffit said:
Just been reading something on the RPi website about pump priming, and then noticed the section below regarding overheating. (about half way down page) [url] www.v8engines.com/faq-gen.htm [/url].

I notice that one reason that your pump may not prime is because the pressure oil relief valve is stuck open in the pump body. I also see that overheating may cause this to happen.

As it happens the car did get quite hot yesterday when sitting in traffic in Gloucester, I was worried about sitting still, but the cooling fans could be heard operating which stopped me worrying too much, though I did turn off at one point.

Could this be something to do with the problem or does this only affect pre-serp cars? If this is a potential problem how difficult is it to check?


I don't know whether yours is pre serp or not.

This is an issue on pre serps, and I have not heard of it happening on a serp engine, although my experience is limted to these pages and gossip ...

If it is a pre serp it may be an issue, but if the pressure release valve had stuck you wuold have seen no oil pressure immediately and both the gauge would have hit the floor and the oil pressure light would have come on ..

shpub

8,507 posts

301 months

Monday 29th January 2007
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The problem is: do you want to risk a potential bill for a new engine on the chance that the instrumentation is at fault when it can be easily checked? That's the issue. I also suspect people are not that forthcoming is admitting in public that I had to replace the engine because I ignored the oil pressure/temp pressure gauge.

It's all about risk managment. As Clint put it a few years ago:

This is the TVR Rover V8... the loudest V8 in the world. Now... was that 0 or 40 psi? You know I can't quite remember. So do you feel lucky, punk?

johno

8,593 posts

311 months

Monday 29th January 2007
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Totally agree Steve, but how many complete oil pressure losses has anyone seen ... A genuine question.

Where oil pressure has gone from good to zero.

I have seen oil pressure release valves stuck, and on the same engine funnilly enough, the oil drive gear from the dizzy snap and cause zero oil pressure.

I totally agree that it is about risk, but chance that it is the engine suddenly becoming knackered, is a small percentage chance in my view ..

spend

12,581 posts

280 months

Monday 29th January 2007
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Hey guys,

This chap is a new owner, read a bit too much in the old testament (brimstone & fire stuff) and got a bit too far ahead of himself so thought the worse. I feel particularly bad cos I answered his earlier thread about priming the oil pump ~ at face value. Theres enough chaps who have had their cars for some time who seem unsure which the oil / ign / alarm leds are..

Lets not give the chap a paranoia until he has checked the oil pressure switch status, and give him a little credit for being safe rather than sorry (or is it discretion before valour?). His newly wed status should be a pleasurable experience, not fraught with worries.

I am sure most of us would first confirm satisfactory operation of the oil pressure light to decide whether it is an instrumentation or engine fault.

Dave

whish I could spell, but I can't, however I try


Edited by spend on Monday 29th January 12:28

johno

8,593 posts

311 months

Monday 29th January 2007
quotequote all
I think you'll find that's exactly my point, fear not the worst scenario as this is the unlikeliest (sp) ....

Most likely a common gauge fault ..

FunkyGibbon

3,858 posts

293 months

Monday 29th January 2007
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When my serp chim decanted its oil on the garage floor (sump plug hanging on for dear life) - it took just over 5 litres to fill her up again.

The oil pump was fine.