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Re: Low Oil pressure.

PostPosted: Fri Apr 17, 2020 6:39 am
by alan.barker
Thanks Matt,
that's what i thought but having sold my +2 i couldn't compare it to my Sprint.
So to remove an Oil Pump it's possible as i said before and the same as Rohan confirmed.
When the 2 Screws that attach the Carb side Engine Mount to the Chassis Lug are removed and Engine lowered.
Just till the Carb Backplate touches the Footwell top.
The location Dia on the Oil Pump that positions it in the Block is not very long.
Once it has disengaged the Block it lets the Oil Pump drop down giving the needed clearance to pass under the Chassis Flange.
Alan

Re: Low Oil pressure.

PostPosted: Sat Apr 18, 2020 4:30 am
by h20hamelan
2cams70 wrote: . I assume of course that you've already confirmed that the oil pressure guage is accurate


An extra gauge and hose is cheap

Re: Low Oil pressure.

PostPosted: Sat Apr 18, 2020 1:59 pm
by 512BB
BW wrote: 'What do they call that tool & where might one get one ?'

Its an oil pump Bill. I inherited it from a dear friend, ex RAF, who ran the Cessna concession at Panshanger airfield, in the 1960's. They looked after Chapman's and Graham Hill's planes there. Good luck finding one the same.

Matt Elan wrote: 'Just a quick note - the front of the Elan and Plus 2 chassis are exactly the same. The only differences are the longer central transmission tunnel and wider rear cross member to space out the Plus 2s suspension top mounts to accommodate the wider track. At the front the Plus 2s longer wishbones do the job.'

Of course, what you fail to mention is the FACT that the engine mounting lugs are welded slightly further forward on a +2 chassis, compared to an Elan chassis, which means that at any given point between the 2 chassis', the width between the horizontal flanges will be WIDER on the +2 chassis.

I wrote: 'The distance between the horizontal flanges on an Elan Alan, is 49.5cm and on the vertical 56.5cm., measured to the centre of the oil pump. The distance on a +2 is 51cm between flanges and 59cm on the vertical, so you coiuld drive the proverbial bus through those differences, in terms of oil pump removal.'

Do you think I just had those measurements floating around in my head Alan? The answer is no. I measured them from a +2 and an Elan chassis I have floating around in my unit!

Nice weekend all.

Leslie

Re: Low Oil pressure.

PostPosted: Tue Apr 21, 2020 9:13 pm
by billwill
Hooray, the flushing oil finally arrived today, and yesterday I cleaned the grease out of the oil/grease-gun that I showed above, so I'm all set to go ahead on a thoroughly clean oil change. The parts from Sue Miller arrived days ago. I bought a new oil-pump, just-in-case.

The dashboard oil pressure gauge is definitely working OK.

One' minor' snag to resolve is that last year while getting ready to go see the old Cheshunt factory, I broke the cam cover cork gasket, so in desperation I cleaned off all traces of sealant and cork and sealed the cam cover to the head with Red Hermetite metal to metal.

It didn't leak any oil but now I have to see if I can separate them again or are they stuck fast. ?? I might have to drill & file an oblong hole in the back rib of the cam cover where it is in contact with the rib on the head, so that I can put a flat blade screwdriver in there and twist to lift the camcover.

Re: Low Oil pressure.

PostPosted: Tue Apr 21, 2020 9:26 pm
by billwill
Oh, bye the way.

When titling the engine to get the oil-pump out, do you need to remove the gear stick to avoid it stopping the tilt due to the 'console' hole?


~~~~~~~~~~~~~~~~~~~~~~~~

As to why use flushing oil? I wouldn't normally bother with this but the behavior seems to indicate that there is some gunge in the oilways and the flushing oil would seem a likely stuff to get it out.

Re: Low Oil pressure.

PostPosted: Tue Apr 21, 2020 11:01 pm
by 2cams70
billwill wrote:Oh, bye the way.
As to why use flushing oil? I wouldn't normally bother with this but the behavior seems to indicate that there is some gunge in the oilways and the flushing oil would seem a likely stuff to get it out.


Usually the cause of the oil pressure relief valve sticking in a pump that's otherwise ok is light corrosion of the plunger in it's bore rather than gunge. The corrosion is best cleared by spraying the plunger with some penetrating oil and working it up and down with a screwdriver.

Re: Low Oil pressure.

PostPosted: Wed Apr 22, 2020 8:22 pm
by Matt Elan
Hi Leslie

You said:
Of course, what you fail to mention is the FACT that the engine mounting lugs are welded slightly further forward on a +2 chassis, compared to an Elan chassis, which means that at any given point between the 2 chassis', the width between the horizontal flanges will be WIDER on the +2 chassis.

Fair enough - if you measured your 2 chassis and there is a difference. But I took the measurments from the Elan and Plus 2 workshop manuals, cross referenced them to a copy of the original Elan chassis blueprint I have and they mounts are in the same place on both chassis - 26.15 in from the datum holes at the bottom of the 'Y' and 7.37 in from the centre of the mount to the chassis centre line, with the mounts inclined at 11 degree s to the vertical.
Just saying.. :D

Re: Low Oil pressure.

PostPosted: Wed Apr 22, 2020 10:51 pm
by vstibbard
have you found out the underlying issue?

Re: Low Oil pressure.

PostPosted: Thu Apr 23, 2020 7:35 am
by alan.barker
It seems the way to go is to first buy a new Oil Pump.
When i bought my last +2 it had been standing for 23 years. I removed the Sump and was surprised to find a deep layer of sludge about 1 cm deep.
Alan

Re: Low Oil pressure.

PostPosted: Thu Apr 23, 2020 12:11 pm
by billwill
vstibbard wrote:have you found out the underlying issue?


I haven't actually DONE anything significant yet. I'm doing some non-car things (programming my Scriptwriters' Toolkit) while I ponder on the best sequence to do things.

I dared to try starting the engine again and the oil prssure went up to 40 psi on the dashboard gauge, but it seems to stay at 40psi and not drop down to about 30 psi. But i don't truly recall how quickly it used to go down to 30 ish. Was that only when the oil really warmed up? On switch off, of the ignition, the oil pressure sank slowly back to zero. It seemed slower than I recall it doing before.

I didn't want it to run long enough for the oil to warm up, because (as I commented above) oil pressure rising to the relief valve figure and staying there might be due to a blockage further along the oilways. I tried to see if there was oil in the cam chamber under the oil cap, There didn't seem to be much there, but on putting a finger in there (with the engine stopped of course) the reachable cam did feel oily.

It will be easier to find out (I hope) whether or not there is a blockage problem when I have a go at getting the cam cover off. But that might be a bit tricky, see above.

Here's a question for those who have used an oil gun or other method to get oil into the galleries. If the oil pump is still in place will the inserted oil backfeed through the pump back to the sump, i.e will it be difficult to get enough pressure through the oil-pressure meter takeoff to feed oil though to the main and cam bearings.

If I strongly suspect (after getting the cam cover off) that there is a blockage in the oil-ways, I am inclined to want to lift the head off and squirt oil backwards down the block to back push any obstruction to the sump and also to take the cams off the head so that I can squirt oil backwards down the oil-ways in the head. It seems like the only way to be very, very sure. Some of you might recall that I have a new SAS head and that runs the cams directly in the head metal with no bearing shells so I really, really don't want to damage those surfaces as fixing wrecked surfaces there would be expensive, involving line boring the cam bearing holes and fitting shell bearings.

Re: Low Oil pressure.

PostPosted: Thu Apr 23, 2020 1:07 pm
by nmauduit
billwill wrote:I dared to try starting the engine again and the oil prssure went up to 40 psi on the dashboard gauge, but it seems to stay at 40psi and not drop down to about 30 psi. But i don't truly recall how quickly it used to go down to 30 ish. Was that only when the oil really warmed up? On switch off, of the ignition, the oil pressure sank slowly back to zero. It seemed slower than I recall it doing before.


The oil pressure at idle depends on several factors, temperature and oil grade being each sufficient to produce the slight change of behavior at the gauge you're witnessing : I would not be worried about that, it shows that the dash gauge works (it returns to 0 after a while when the engine is cut off), and that the pump works (tha gauge shows pressure when the engine runs). If the engine is relatively new and tightly built, with a cold thick oil the oil pressure may not go back to 0 immediately.

If you havent taken the camshaft cover off, it it not practical to verify if the oil pockets in the head are actually full of oil (taking off the cam cover would be my next step to make sure the cams are properly lubricated - both sides) - yet I would run the engine till the coolant warms up, not over revving by precaution, but for say a minute or two, listening carefully from being near the open lid if some new noises are coming up... to be over cautious you can do 30 sec at first and try to witness camshaft lubrication, then again for 1 or 2 minutes. It is very possible that all is fine for now...

It is indeed difficult to get oil pressure with a manual means, the intent is to get some oil everywhere so that the film prevents metal to metal contact at first, then the pump provides enough flow and pressure to go on (unless one makes use of an accusump or something the like). If you have a blockage it is unlikely imho that you bak backwash it (unless a conical bit of silicone that has travelled in the oil and happens to be stick at a restriction of an oil gallery).
If you are at the point of taking the head off a complete clean up will provide you the assurance you need to restart (blowing air through the galleries etc).

Re: Low Oil pressure.

PostPosted: Wed Apr 29, 2020 11:29 am
by 512BB
I had a few minutes to spare yesterday, so I will update this chassis thread :lol:

[quote="Matt Elan"

You said:
Of course, what you fail to mention is the FACT that the engine mounting lugs are welded slightly further forward on a +2 chassis, compared to an Elan chassis, which means that at any given point between the 2 chassis', the width between the horizontal flanges will be WIDER on the +2 chassis.

Fair enough - if you measured your 2 chassis and there is a difference.

Thats right Matt, I did and there is.

I took a couple of pictures of two more chassis' that I have in stock. This time I took measurements at the engine mounts, whereas before, I took measurements from where the oil pump would sit. On the +2 chassis, the gap to the vertical faces is 53.5cm and on the Elan chassis, the gap is 52cm.

On the +2 chassis, the gap to the horizontal flanges is 45.5cm, and on the Elan chassis, the gap is 43.5cm. and I make that a 2cm difference, Massive, in terms of oil pump removal.

The workshop manual and Wilkins book have both been proven to be incorrect in places, and there is no doubt in my mind that your blueprint Matt is similarly flawed, if it shows the engine mounts in identical places for both the +2 and Elan chassis', they are not.

Let me know if you would like any further chassis pictures or measurements.

Leslie

Re: Low Oil pressure.

PostPosted: Wed Apr 29, 2020 12:46 pm
by pharriso
What's your point Leslie? Yes the chassis may be wider on a Plus 2 but so what? the OP wanted to know if the Oil pump can be changed on his S4 with the engine in the car.

The answer is still yes it can. How do I know? I did it on my own car in early March.

Stay safe!

Re: Low Oil pressure.

PostPosted: Wed Apr 29, 2020 1:41 pm
by alan.barker
Hi Phil,
+1
Alan

Re: Low Oil pressure.

PostPosted: Thu Apr 30, 2020 12:52 pm
by billwill
It's an S3 coupe actually, not S4

But anyway Leslie was just being good enough to clarify an issue that arose from other answers, not my original posting. Essentially to the effect that you can't get the oil pump out of a 2-seater without moving the engine, whereas you can (maybe) get it out on a Plus 2 without moving the engine.