Oil Change Problem

[Michael Oritt]

Something happened yesterday that has me a bit perplexed if not concerned:

I drained the engine oil and removed the spin-on oil filter, then after about an hour reinstalled the drain plug, mounted up a new filter and filled the engine with oil, all as per usual. I switched from 10-40 to 20-50 for the summer.

I then started the car, watching to see the oil pressure needle go up and the low oil pressure light I installed (10 psi threshold) go off, but after about 10-15 seconds the needle was still pegged and the light still on. A couple more tries produced the same result.

I removed the oil filter, which mounts horizontally and saw that it was still empty, which told me that for whatever reason the oil pump was not delivering oil. Thinking that the pump may have lost its prime I removed the pipe that goes to the OP gauge at the block and squirted in oil hoping to reprime it. I started the engine but still no oil pressure.

Finally I clamped off the vent hose from the valve cover, disconnected the coil wire, removed the oil filter and while a friend cranked the engine I pressurized the sump with high pressure air through the oil filler until I saw oil coming out of the block where the filter mounted. I then reinstalled the filter, reconnected the coil and started the engine--after a couple of seconds the OP came up and everything was fine.

My question is: What happened and why? Obviously the oil pump lost prime and would not reprime itself but this has never happened before, even after the car has sat for long periods with no engine oil whatsover. I am beginning to suspect that the pump may have seen better days--though my OP is good at running speeds (50-60 psi) it does go down to 10-15 psi at idle.

BTW I see that Moss says that oil pumps for 100's are NA and in any case I am skeptical of County stuff. DW wants about 250 pounds for their oil pump. Are there any other sources?

 

[vette]

Mike, That's a tough one but do you think it could have been the filter. I have been surprised at times when I change my filter that it seems like there is no oil in the old filter. (Spin on with Moss adapter) Its horizonal position seems to allow the oil to drain out quickly. In rebuilding a few engines and sometimes forgetting to put in a gallery plug or connect a pipe, I am always amazed at how much pressure a pump puts out. even an old pump. It's been my belief that low pressure at the guage is caused by bad bearings not a pump. So I wouldn't suspect the pump. Yet I am not familiar with the innards of the Healey engine, so maybe a pump to pipe or pump to mounting has come loose or blown a gasket. I use 20w-50 oil now for the first time. Have been using straight 30w. I have very good pressure, more that I am use to. One last thought, are you sure you have enough oil in it during your first attempt. Dave.

 

[Michael Oritt]

Dave--

There was plenty of oil--7 quarts.

About the filter: I used a K & N 2009 which I have always in the past without a problem. However the filter is mounted horizontally and I cannot fill it prior to installation which I am not happy about as it theoretically puts a big slug of air into the system.

(I also use K&N's on my race cars--a 2009 on the Courier/MGA engine and a 3001 on the MK IV/Climax engine--and since both of them are vertically oriented I can fill them before installing.)

I just started the car for the first time since yesterday and while my running oil pressure is about the same--60 psi with a cold engine--the pressure remains at about 50 psi even with the engine idling!

I'll keep a close eye on things and if I have any problems whatsoever I will not hesitate to drop the pan and inspect the oil pump and connections, etc.

 

[GregW]

As I recall, the 2009 has an anti-drain feature.

 

[John Turney]

Most cartridge filters have anti-drain membranes so they can be filled and then mounted horizontally.

 

[GregW]

Well the 2008 k&n I have doesn't.

 

[Bob_Spidell]

Any chance a stuck relief valve could cause this (don't have the oil flow schematic handy)?

 

[Michael Oritt]

In fact I had the relief valve out while changing the oil, etc. and I made sure the plunger was clean and seated properly. Perhaps that was not the case previously--that the valve was slightly off the seat, and when I came to idle speed a lot of the oil/pressure was escaping around the valve which might account for the low oil pressure at idle?

 

[Bob_Spidell]

In fact I had the relief valve out while changing the oil, etc. and I made sure the plunger was clean and seated properly. Perhaps that was not the case previously--that the valve was slightly off the seat, and when I came to idle speed a lot of the oil/pressure was escaping around the valve which might account for the low oil pressure at idle?

Possible. Have you checked your OP with a calibrated gauge? I had the safety gauge on my BJ8 refurbished and, presumably, calibrated, and 'gained' 15PSI at idle.

 

[Michael Oritt]

Bob--

That's a timely suggestion as I have to pull the safety gauge and send it off to Nisongers--somehow the ammonia escaped from the water temp sender bulb/line.

 

[Bob_Spidell]

I believe the substance used in the temp gauge is ether.

 

[Michael Oritt]

I believe the substance used in the temp gauge is ether.

Right you are Bob. BTW I found an interesting page on MGA Guru telling how to make the repair using a different substance: https://mgaguru.com/mgtech/dash/dt102a.htm. That said I think I will stick with Nisonger.

 

[Bob_Spidell]

Funny/almost tragic story: my dad tried to repair our gauge himself. He bought ether--surprisingly, available at a drug store--filled the bulb, then attempted to solder it sealed. Well, ether is extremely volatile--hence this use--and flammable as well, and the predictable happened: the bulb shot across our barn at high velocity. Fortunately, it didn't hit my dad but, as the bulb is roughly the size of a 50-caliber it could have caused major injury.

The gauge went to Mo-Ma.

 

[glemon]

I have "restored" oil pumps successfully and brought pressure up with the method described for getting the rotor to body clearance correct here: https://www.automedia.com/Oil_Pump_Restoration/res20010701op/1 there are two areas where wear is a concern, the edges of the spinning rotors, and the base of the rotors or vanes on the bottom of the pump, you can improve base to rotor clearances by carefully sanding the body of the pump down a bit, I have done this and have also know others that have done this and gotten appreciable increases in the oil pressure, of course the area where the most wear has occurred in the pump will of course make a difference.

 

[Healey Nut]

I have "restored" oil pumps successfully and brought pressure up with the method described for getting the rotor to body clearance correct here: https://www.automedia.com/Oil_Pump_Restoration/res20010701op/1 there are two areas where wear is a concern, the edges of the spinning rotors, and the base of the rotors or vanes on the bottom of the pump, you can improve base to rotor clearances by carefully sanding the body of the pump down a bit, I have done this and have also know others that have done this and gotten appreciable increases in the oil pressure, of course the area where the most wear has occurred in the pump will of course make a difference.

Yep it can be done all you need is a piece of glass of reasonable thickness say about 1/2" and some good ole valve lapping compound ....oh and time and patience ...

 

[BoyRacer]

Michael,

You are not alone. I believe I once had the same experience as you. I don't recall exactly what lead up to it. It was with my 3000 race car. As you know, with race cars we are always doing and undoing things, like oil filters, oil coolers, oil lines , etc. Sometimes pulling the engine for some darn reason. So, the one time that I recall where I could not get oil pressure after about 15 seconds, I started to go bonkers......what did I do, what did I change....re-analyzing everything. Finally, I just fired it up and after another long 10 seconds or so....bingo. Great oil pressure.
On fresh engines I usually pack the oil pump with some petroleum jelly just to help things along.

 

[Legal Bill]

How many miles on the engine? Oil pan sludge will not drain out of the pan, but it will ooze to the rear of the pan and get "dehydrated" as the thinner oil drains out, especially given the 1 hour duration you wait to stop the draining process. Once it has all built up around the oil pick-up tube the pump will have a difficult time picking up oil. The air pressure probably pushed it in.

Back in the old days at the shop we would sometimes have to drop the pans and scrape them out to get rid of the sludge.

 

[Michael Oritt]

Bill--

About 50K since rebuild. Good thought and since I am going to drop the pan in any case to check on the OP clearances I will have a chance to inspect for sludge and clean if need be. Thanks mucho

BTW what about source(s) for a new oil pump should it come to it. As I said in my first post Moss shows pumps for 100's to be unavailable and in any case I am suspect of any County parts assuming that is where it would come from. DW wants a king's ransom for one. Are there any alternatives?

Best--Michael

 

[Legal Bill]

I'm no help on that question, Michael. Healey Surgeons lists one for $500!!! You might call British Car Specialists and ask them what they are carrying. BCS lists theirs as "upgraded" whatever that means. No price shown. I have no idea what HS has

I bought a new oil pump for my BJ8 from a Moss-like supplier when I rebuilt the engine and I am not impressed with its performance. If I was doing it again, I'd probably spring for the better one. At current exchange rates the DW pump would cost $385. That is pricey, but less than HS. If the alternative is junk, then I'd go with it.

 

[Randy Forbes]

Castrol Oil won't turn to sludge; Quaker State will develop sludge in just several thousand miles. Talking pre-synthetic here.

I've had the opportunity to go back inside engines I've (built and) run on a steady diet of Castrol oil, and you can wipe the inside of the crankcase out with a paper towel and it's very nearly as clean as when it was put together.

Quaker State formed a "bonnet" of sludge inside the rocker cover of an MGB in the 6k or so miles between valve checks. I wouldn't have ever tried the QS, but back in the 80s, they had a promotion going where they'd supply you with FREE OIL and FREE ANALYSIS for one (1) year. I was convinced, and switched back to Castrol, but I have kept up with the oil analysis (on ALL my cars) ever since.