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no initial oil pressure TC

PostPosted: Sun Sep 23, 2007 4:50 am
by rdssdi
As my Elan +2 restoration nears completion it is time to start the engine. It was rebuilt by Marcovicci and Wenz (U.S. engine specilaists) several years ago. They "pickled" the engine after dyno testing.

I removed the plugs and added some oil to each cylinder. I removed the valve cover and poured oil over the cams, tappets and chain then replaced the cover. I removed the oil pump and primed it with fresh oil and replaced it. I replaced the oil filter first filling it with oil.

As the plugs are out I turned it over with the starter while observing the oil pressure gauge. I get no pressure and upon removing the pressure sender there is no sign of oil. The oil pump is new as part of the rebuild. I assume M & W saw oil pressure when running the eengine on the dyno.

What do I do next? I am concerned that I may have damaged the bearings but without the stresses of compression that is somewhat mitigated.

HELP!

Bob

Re: no initial oil pressure TC

PostPosted: Sun Sep 23, 2007 6:43 am
by rgh0
Bob

Turning the engine over without oil pressure and the plugs out will do the bearings no harm. The oil film left on the bearings is plenty to lubricate in these circumstances.

Make dure when you remove and refit the oil pump that it seats and seals properly on the block, a small air leak to the pump suction side and it will struggle to ever pick up oil from the sump and develop pressure. Some people prime the pump with a thicker substance such as grease or vaseline rather than oil to aid pump priming, if doing this I would use assembly lube as it is designed to be compatable with engine oil

You can repeat what you did and try again and see if you get pressure, it can take a few tries of pump priming and a lot of cranking to finally fill the system and develop pressure.

Alternatively get a pressure container you can fill with oil and pressurise with air and fit up a line to the pressure gauge tapping on the block and fill the oil system using this method. This guarrantees you have oil at the bearings and generally minimises the time required to build pressure.


regards
Rohan

oiler

PostPosted: Sun Sep 23, 2007 10:25 am
by rdssdi
Where can I purchase a suitable pressure container to "pre oil" the engine. I cannot find any at parts suppliers.

Bob

Re: no initial oil pressure TC

PostPosted: Sun Sep 23, 2007 10:45 am
by rgh0
Bob

I have never seen any standard commercial units though they may exist.

The one I have borrowed a few times from the The Elan Factory is made from a modified 5 kg LPG gas cylinder.

More recently I have used a spare accusump unit that I took off my Elan when they banned them for historic racing here.

There are a variety of plastic bottles designed to be pressurised for spraying weedkiller or similar and it may be possible to modify one of these also.

cheers
Rohan

sprayer bottle

PostPosted: Sun Sep 23, 2007 1:24 pm
by rdssdi
I saw several refeerences on the internet to modifying a pump spray bottle such as used to apply liquid pesticides. I will remove the spray wand and add a 3/8" npt swivel fitting.

I hope my memory is correct and the oil pressure sender port is 3/8 NPT.

Bob

no initial oil pressure TC

PostPosted: Sun Sep 23, 2007 6:11 pm
by 264889socal
Another was is to use a flexible spout pump type oil can. The flexible nozzel allows you to fit it to the fitting coming out of the block with ease. will make a little bit of a mess, but if held tightly works pretty well. Pump the lever until you start getting lots of resistance and you can pretty much be assured all of the galleries are filled with oil. Continude pumping will get oil to the bearings.

Rob Walker

Re: no initial oil pressure TC

PostPosted: Mon Sep 24, 2007 10:32 am
by rgh0
Bob
Blocks had 2 different size oil pressure tappings, a small and large one. Not sure off the top of my head what they were but maybe 1/4 and 3/8 NPT. You need to check what you have.

regards
Rohan

pressure at last

PostPosted: Tue Sep 25, 2007 1:40 pm
by rdssdi
I purchased a 1 gallon pump spray bottle such as used for pestacide application.

When I assmbled it, I left off the spray wand. The flex hose was a good pressure fit into the 3/8" female elbow that accepts the oil pressure sender. I pumped in oil, cranked the engine for a brief moment, then pumped in more oil. I refit the oil pressure sender and cranked again. I immediately had very good oil pressure.

I now have to do the distributor timing and it will start.

Bob

Re: no initial oil pressure TC

PostPosted: Wed Sep 26, 2007 9:39 pm
by alaric
Hi.

I had the same problem with my qed built tc - sat for 2 years before I managed to get to turning it over, then could get no oil pressure.

To verify that the oil pump was working I cranked the engine ( with no spark plugs in) with the oil filter removed, until oil poured out into the carefully placed receptacle - it did take maybe 10 to 20 secs for the oil to appear. This at least showed the oil pump to be working. That was an extremely stressful 20 secs!

I then popped the oil filter on and hey presto had pressure. Big relief.

I think the oil pump had drained and wasn't able to force the oil up the galleries.

Sean.

Re: no initial oil pressure TC

PostPosted: Mon Oct 01, 2007 12:52 pm
by Bruce Crowthorne
Hi Bob, I had the same concern. I even tried getting my son and his pal to push me up and down the road in the car, but with the plugs out and in second gear (wasn't kind enough to do it in fourth!).
After a total of several hundred yards I gave up.

I put the plugs in and started it on the key (heart in mouth etc) and after a few (very worrying) seconds the oil pressure came up.

Like you I had primed the pump, put oil in the galleries, filled the filter, but none of these seem to have helped.

Hope you get your twin cam going soon
Bruce

Re: no initial oil pressure TC

PostPosted: Tue Oct 02, 2007 8:34 am
by Keith Scarfe
I too have suffered from this before. Particularly if the car has sat for a long while over winter for example, and always after an oil change. I don't know why mine is particularly bad but is seems that the oil drains right out and no matter how much cranking I give it with the plugs out , the pressure doesn't come up.
Here is my solution. You will love this one.
Take off the oil pressure gauge feed pipe at the block so the male to male adapter is still in the block and get a piece of rubber hose that is a tight fit over the male thread - like a hose over the bleed nipple when bleeding the brakes. Then crank the engine wile sucking on the rubber hose with your lungs. A clear pipe is good so you can see when the oil starts to come up. When oil is there connect the gauge and he presto - oil pressure.
A bit of a bizarre way of doing it, but it works for me anyway.

Re: no initial oil pressure TC

PostPosted: Tue Oct 02, 2007 8:35 am
by Keith Scarfe
I too have suffered from this before. Particularly if the car has sat for a long while over winter for example, and always after an oil change. I don't know why mine is particularly bad but is seems that the oil drains right out and no matter how much cranking I give it with the plugs out , the pressure doesn't come up.
Here is my solution. You will love this one.
Take off the oil pressure gauge feed pipe at the block so the male to male adapter is still in the block and get a piece of rubber hose that is a tight fit over the male thread - like a hose over the bleed nipple when bleeding the brakes. Then crank the engine wile sucking on the rubber hose with your lungs. A clear pipe is good so you can see when the oil starts to come up. When oil is there connect the gauge and he presto - oil pressure.
A bit of a bizarre way of doing it, but it works for me anyway.

Re: no initial oil pressure TC

PostPosted: Thu Oct 04, 2007 3:41 pm
by tdafforn
Hi All,
looks likeI am having the same problem..
New rebuilt twink, no oil pressure on cranking..
Have used a large syringe to push oil into the engine through the oil pressure sender fitting until it appeared on the camshafts. Filled the oil pump with graphogen, cranked on the battery, no oil pressure..
Should I go for the heart in mouth method and just start the car?
Cheers
tim

Re: no initial oil pressure TC

PostPosted: Thu Oct 04, 2007 5:40 pm
by john.p.clegg
Tim
Firstly short out the wire on the pressure sender to earth and watch the needle cross the scale,this will eliminate faulty wiring gauge etc,but unfortunately not sender...

John :wink:

Re: no initial oil pressure TC

PostPosted: Thu Oct 04, 2007 6:32 pm
by tdafforn
Hi John,
Good thought, but the sender is a capillary type. I currently have it unplugged with the hope that evidence of oil spurting out of it will be a good sign that the pump is primed.
Is this a good idea?
Cheers
Tim