Hello Folks,
I just finished rebuilding an XK 140 engine. It has a new oil pump installed. I primed the oil system first by using a oil external oil pump to pump moil through one of the oil gallery plugs. I pumped until I had oil coming out through the cams. When I tried turning it over with the starter I found no oil coming up through the line that feeds the cams. Next I took off the oil filter housing and found a tiny bit of oil coming through the hole that comes from the output of the pimp to the housing. The only thing I can think of is that the pump is bad or that it isn’t picking up oil from the sump. Perhaps it is air bound? I am really flummoxed. Any one got any ideas before I pull the oil pan off?
My car had not run for many years . I couldn’t get any oil pressure turning on the stater. I started the engine and the pressure came up immediately. Bit of a risk but it worked for me.
Are your plugs out? My 3.8 was able to develop measurable oil pressure off the starter with the plugs out but it took some grinding to make it happen, like ~30 seconds worth. It cranks very easy and fast with no compression.
You could also loosen one of your cam feed lines and put a baggie over it. Crank the starter and see if oil shoots out. So long as you have some oil in the cam galley that will be fine.
Hi Folks,
Thanks so much for the support. The picture that Rob posted is where I am at. I have the filter housing off and am looking at the lower left hole. I do get blurps of oil coming out the lower left hole (from oil pump). They are very intermittent and not much volume. I do have the plugs out and have a huge battery spinning over the engine with a high torque starter. It is spinning pretty fast and strong. I will try starting it and report back probably not tonight. I need to sleep on it.
Hello again,
Would it be helpful to put extra oil in it temporarly? I figure the pump is having trouble picking up the oil from the sump? What else could it be?
How much oil did you add? I’m not sure at what point the level is below the pickup but that’s a very big pan and the pickup is not right at the bottom.
I posted about how long it took for my fresh rebuild to show O/P some months ago…from memory 15 or twenty seconds till pressure reading on a gauge mounted to the gauge port on oil canister…another 20 or so till oil was seen in cam area.
Found my old post…18 seconds from full drain-down(2 weeks of sitting) till I got some pressure reading…another 7 seconds to show 35 psi, then 15 more seconds till I saw oil at cam bearings.
The pick-up suction tube should be sitting 3/16" to 1/4" off the bottom of the sump so even just a few quarts will feed the oil pump.
Try cranking for at least 20 or so seconds next time(plugs out).
Pick up pipe o rings?
I forget, is there a pin on the pump shaft to drive the inner rotor? I’ve seen that(missing) happen in a past life.
Wes, did you pull the pump apart and measure tip clearance & outer clearance?
Hello Folks,
Thanks to all for the advice. To answer some of the questions folks raised:
Initially I put ten quarts in.
2.Yes I installed O rings and the pipes fit snugly into and out of the pump. The pump is turning as I am getting some oil coming out the hole in the block. The pump is brand new so I didn’t bother to check clearances.
3.Wiggles I totally agree with you, the oil should be gushing out the hole in the block directly from the pump. I was very careful to make sure the inlet pipe lined up with the screen in the bottom of the sump and that both pipes were clean and solid.
I bought 10 more quarts of oil and will install that tomorrow. My thought being is that the oil might cover the pump entirely with oil and eliminate the possibility that there is a problem with the pickup tube. If all else fails I guess it won’t be too bad to pull the sump off.
Thanks for listening and commenting.
10 quarts is already over capacity. I wouldn’t add more to that unless you’ve already pumped out several quarts at least. What’s your dippystick say?
One part that I found was missing on mine was the small gasket between the pickup tube and the block. Did you put that in? It won’t make a good pressure seal without it. What sort of work was done prior to this? Was it a full rebuild, and were the oil passages blown out?
These pumps are positive displacement. Unless the supply of oil is restricted at the inlet, or the suction line in not submerged, it will self prime and pump. So long as the suction tube is attached, there is no need for the pump to be submerged. The oil pump is driven from the opposite end of the same shaft that drives the distributor. Step #1 would be to verify that the distributor is rotating. It is possible to put the pickup too close to the bottom of the sump, blocking of the suction line. That typically results in pump cavitation, which is quite noisy.
I thought our xk engines took about 13 qts, plus one for the filter housing. If you only out in 10 total the. You only have 9 in the sump. If I’m right about the 13qts the. You are 4 qts low and you might be sucking up part air when you crank it over.
And are we talking Is or imperial quarts (20% difference)?
14 quarts is correct. He has 10 in already…no chance that there is not enough oil. Mike said it, the pump will self-prime…period. I doubt you could have even got the sump installed if the pick-up did not engage properly with the strainer basket…Just make sure the sump is not dented up so badly it blocks flow to the pick-up. I measured and test fitted mine before final assembly to verify this clearance was correct. There is a gasket between the oil supply tube and the block passage, but even if it were completely missing, you would still get lotsa oil shooting out the proper hole…path of least resistance.
