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BJ7 correct oil pressure

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chicken

chicken

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Just fired up the car for the first time, the oil pressure gauge is connected to the pipe from the block but on running for 60 - 90 seconds there is nothing showing on the gauge.
Does the engine need to run for a certain amount of time to build up the pressure (especially on it's initial start up), i trust the gauge has no wiring going to it !
Again there was no real movement on the temperature side but can't say i would expect any in that short a time.
Oh and yes the gauge has been supposidly been reconditioned (but going on past experiences of other recon parts you cannot allways rely on this).

Help needed.

Rob
 
Rob,

You can always check the Oil pressure gauge with a little air pressure. If the gauge seems to work OK and all the connections are tight I would try cranking with the starter only. You should be able to build some pressure.

Prior to starting for any period I would make sure you have pressure.

Case in point I have a 100, so it's different but I was able to get 40 psi on the gauge with the starter only and was able to verify oil getting to the rockers and top end before starting.

Good luck - Hope this helps
Michael.
 
Hi Rob,
Did you pack the oil pump with anything when it went in? Some people have used vasoline, I made a mixture of assembly lube and oil. This would be to help prime the pump.
 
Michael

Guess i better check the gauge first, do you just blow some air into where the oil pipe goes in ?, don't you have to be carefull of the pressure.

Rob
 
Greg

Is there another way of priming the oil pump when it is fitted, i was then looking back at my invoices and don't believe i ever fitted a new pump as there didn't seem alot wrong with the old one after a clean up !

Rob
 
If the test air pressure is less than the gage maximum, no problem.

When the sump is filled with oil the pump is submerged. Normally, the pump will fill by gravity pressure if given enough time. Oil seeps in & air is driven out, albeit slowly. I've always found that a couple of hours with the pump submerged is more than adequate to fill the pump.

Most important would be to pre-fill the oil filter, when installing it, so that the pump doesn't have to fill it before pressure develops.

Even upside down & horizontal mount filters can be pre-filled & then quickly inverted & mounted without losing too much oil. Provided that the filter has a good anti-drainback valve.

If everything is working correctly, including the gage, pressure should show within 30 seconds of starter cranking before the engine is actually fired. Usually more like 10 seconds.

If you can't build pressure on the gage by starter cranking only, coil disconnected, there is something wrong. Do NOT fire the engine.
D
 
I agree with all that has been said and will only add that you may pull the spark plugs when you crank with the starter. You will crank faster and may crank for a bit longer, as it takes less juice. You can put a squirt or two of engine oil in each cylinder to give a little top end lubrication. Dave is correct as usual with the 30 second time frame, but that is a lot of work for your starter when it is working against compression.
 
Dave

Thankyou for your pointers, i will check the pressure gauge at the weekend then fill the oil filter up and see how we go from there.
In your opinion is there alot that can go wrong with the pump ? i never replaced mine but just cleaned it up.

Rob
 
Chicken,

Had the same problem after a rebuild of my BJ7. Pull the filter head from the block. One of the holes under the filter head goes directly to the oil pump. Use a pump type oil can and pump oil into this hole until oil starts to run out. Install filter head and fill canister with oil.

You should immediately have oil pressure indicated on your gauge.

Ray
 
Rob,

My BJ7 is fitted with the spin-on filter. I assumed you had the canister type filter. In the case of the spin-on, fill the filter with some oil and refit. If your oil pump is in good condition, you should see oil pressure within a few seconds.

Let us know the outcome.

Ray
 
Ray

So iv'e just come out of the shed and still have no oil pressure, i have done the following:

Filled the oil filter with oil and pumped some oil in the 2 holes until it came out again (only took a few squirts !)

Checked the pressure relief valve, seems free enougth.

Had the rocker cover off and oil was coming up through the rockers and going down the lifters.

Pressure checked the gauge with some air and it seemed to work ok.

So any ideas why i can't get any pressure now, doesn't seem to be any external leaks !


Rob
 
Hi Rob,
One thing you may want to try is bleed the oil line to the gauge. Remove the line at the gauge, have a rag handy to catch squirting oil, and crank the engine (Don't try to start it). When you get oil, stop cranking and re-attach the line. Don't forget that tiny washer.
 
Rob,

Forgot to ask if you are sure that you have the conversion filter head the right way round. The hole coming from the block MUST be lined up with the correct hole in the filter head. Is very easy to install the head incorrectly. You must insure that the hole that goes from the block to the oil pump is the hole that is lined up with with the hole that goes from the head to the filter body.

Keep us informed.

Ray
 
Rob,

Just re-read your last post. If you are getting oil up to the rocker assembly the oil pump must be working. Have you tried disconnecting the oil pressure line from the block and turning the engine with the starter. That is the line that goes from the block to the oil pressure gauge.

Ray
 
Ray/Dave

Iv'e just had the threaded adapter out of the block and yes the little hole was blocked.
Unblocked it and put it all back together but still nothing !!
Ray you say about removing the oil pressure pipe, well i had this disconnected the other day while turning it over and nothing came out, i'm now wondering if it may be a bit blocked/gunged up where the adapter threads into the block ?

Oil feed is going to the rockers but there are about 2 that are not getting oil, however i guess this is just a case of misalignment on the rocker shaft or holes in the bushes slightly out (which i can come back to), this wouldn't cause lack of pressure would it.

I did notice what looked like air bubbles coming through the rocker feed, is this normal.

If i added a bit more oil would this help things along.

Rob
 
With the oil pressure guage line disconnected at the block and coil disconnected so that the engine won't start, do you get any oil coming out when you turn over the motor with the starter? Careful!!! Someone should watch while another turns the starter over so that you don't get a mess of oil out. If yes, then clean out the oil line pipe and flex to the guage. You could even but a cheap guage to temporarily check out the pressure.
 
Shorn

No on removing the pipe from the block and turning over on the starter with the plugs removed i had no evidence of oil ???

Rob
 
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