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oil pump she nowa pump

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anthony7777

Yoda
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over the last several weeks my oil pressure began to slowly drop off,thats a good thing at least the engine didnt suffer a suden catistrophic failure,i removed the oil press guage line and put a regulated 40 p.s.i to it and its working dead on, ive pulled the pump this morning,but all i had time to do was crack this puppy open, the one on my car, 63 bj7- has the double gear unit, my healey repair manual only shows the required clearances for the older sing gear type,anyone know the tolerances for this type? i know im going to have to buy a new one anyway since there is gauling on the inner surfaces that appear deep even to the naked eye, in particular the bottom of the housing that the gears slip into. oh ya forgot to mention the $230.00 replacement.im simply interested in knowing how close the measurments should be, thanks, a7777
 
/bcforum/images/%%GRAEMLIN_URL%%/whistle.gif 7777;

Gear Type Pumps:

End Float Max =0.005"

Oil Pump Gears to Body Max =0.002"

Cost! Will not change.---Keoke- /bcforum/images/%%GRAEMLIN_URL%%/laugh.gif
 
I would think the oil pump would continue to produce volume/pressure until total (or driven shaft) failure.

You're not overlooking the possibility of a worn rockershaft causing the loss of pressure? That's an easy one to check; do you get a shower with the rocker cover off and the engine running?
 
I was suprised when I stripped my gear pump out to find it measured in spec despite the rather low pressure when hot. I replaced it with a vane type unit and since then everything has measured normal even when very hot.
 
randy, no with the rocker cover off it does not "sprits" but i also noticed that along with the gauling at the bottom of the pump housing the two holes in the top cover that hold the shafts for the gears are slightly elongated,to be honest even in this condition i agree/feel the pump should still produce some pressure as it still rotates rather easily,when i get a chance im going to drive the pump with an electric drill and see what it does,as mentioned here i might be looking at a rocker shaft replacement.whats your take on this one?
 
randy,keoke was kind enough to give me the specs on my type pump it i checks out ok, i reassebled the pump submerged the pick up end in a large container filled with oil and while usind an adapter i made from an old 1/2" paddle drill bit and a cordless drill i turned it over, even at very low rpm this thing pumped like a saudi oil rig, i did remove the oil pres. release valve and replaced it with a new one, perhaps the press. is getting by it since the old one is disfigured see atch.and perhaps its seat in the block as well.
 

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The symptoms of pump wear & or relief valve plunger leakage would be reduced idle & low rpm oil pressure that comes up to near normal at higher engine speeds. Low pressure at higher engine speeds is often caused by a weak relief valve spring.

I believe that pump bottom cover to gear clearance would be better at .002" rather than .005". The wear on the bottom cover will definitely reduce idle pressure. Relief valve plunger & seat leakage will definitely lower idle pressure.

It may possibly help to tap/seat the new plunger into it's seating surface with a wood dowel. If the engine were totally apart so that you could thoroughly clean the grit out, lapping the plunger into it's seat might help some. The relief spring can get weak & replacing it with a new longer spring or shimming the old one about 1/4" may help.

The grooves in the bottom cover can be removed by lapping it on a glass plate ot having it surface ground. The same can be done to the bottom of the pump body if gear to cover clearance is excessive.

It may be simpler to just replace the pump, but not all new pumps are that much better. A new pump won't help much if the relief valve is seriously leaking.
D
 
7777, What do you mean by; "The old one is disfigured" ?--Keoke
 
keoke,its difficult to discern from the pictures but the p.r.v. on the left is indented just below the top (the shiny ring) near the middle of its conical circumference and is pitted,as a test i made every effort to securely lodge both of these idividualy in the block with much heaver spring then required-still no pressure,im going to see virginia today and pick up the new pump,ill test it well see what happens then,worn cam bearings,rocker assembly.??? im not looking fwd. to these projects right now!
 
OK Anthony, That indentation [step] on the nose defines the correct valve for these engines. However, if it is severely pitted its got to go! The one on the right will work but may take some fiddling with the spring. Roger Moment wrote an article a few years back that clarified the differences in the valves and the impact of P.R.V malfunctions on the engine as seen on the guage.I do not know who at the present time carries the correct one. Maybe British Car Specialties.---Fwiw-Keoke
 
keoke, you are correct the press. re. valve in an m.g. looks the same but upon examination will not have a shoulder/step in it as does the one for the healey, i got one from virginia and the new pump today having cleaned everthing up one can stick ones head between the r/s frame rail and the block and look into the hole that the valve fits into, doesnt look as bad as i thought since the sump is off im going to "lap" the valve in a bit and see what she looks like, should have been able to start her up about 1/2 hour ago but found someone pre. had broken a sump bold in its hole the one closest to the tranny "of course" couldnt have been one in the open field right, should have it tightied up some time in the new day, thanks,a7777
 
Oh! that make me so jealous,all I can do is talk to her on the E-mail. Got a note from her this week telling me they moved the store down the street but ended up in another town Stamford. See ya later-Keoke
 
shorn, sorry bud id mist your question till just now, to answer it- no- the oil pressure started to bleed of over several weeks id been driving the car just about every day until last week, it dropped from 47-52 lbs. to 25-30lbs. then 15-lbs-0 in a three week period, in all this time if i stepped on the gas the pressure would rise then fall with the release of the gas pedal, i believe this to be an indication of 1-bad oil press release valve,2-bad oil pump,3-worn rocker assembly,4-poor cam bearings,im approaching the problem in that order, ive got the new pump in last night and plan on "lapping" in a new p.r.v. today,also have to drill out and retape a broken sump bolt that the pre. owner was nice enought to leave for me.i hope to be able to run it this afternoon, keep ya fingas x,thanks, a7777
 
Well, since you have the oil pan off to get at the oil pump, why don't you pull a rod cap or two and check one or two of the rod bearings. If you see a copper color on the bearings, that indicates significant wear. They should be a silvery color. If the rod bearings are worn, so are the mains. Since this happened over 3 weeks maybe something got into the engine that buggered it up. Anyway, I hope the bearings are OK. If not you're looking at a fairly big expense.
 
keoke,randy,dave,shorn,andrew,this afternoon being amift of my oil press.dilemma i decided to eliminate any problem that might be associated with the dasterdly o.p.r.v. being a master cabinet maker i reverted to my wood working skills and produced a wooden valve (maple dowel) that would most securley fit and seal the orifice, i then started the "beast" and to my consternation noticed the guage jump to 55lbs momentarily then drop to zero, i have since decided to forgo any further exploration of automobiles and return to romancing and building wooden boats instead! "babe please fix me an additional rum and coke"
 
If you still had the spring on top of the "valve", It's likely that the valve seated until the pressure opened the valve & then the valve stuck open. It takes a very precise but free sliding fit on the valve. Wood is not "that" precise & has a lot of friction.

If you were to make the wood valve long enough that it bottomed out in the block before the cap threads were fully home, no spring, it would hold the valve firmly against the seat.

Don't give up now.
D
 
dave, what i did was shape the dowel as well as i could, its about 6 inch. long, i then gently drove it into the opening securley enought to seal the orifice,no spring, no cap,im certain it fully closed and sealed,am i missing something? i believe the stronger the spring-the greater the press. would be,the weaker the spring-the lower the press. will be, so if one would totally close off the the valve seat the press should be high? perhaps my dislexia? is showing? thanks for your support,im truly not that tragic perhaps just a bit dramatic, cant help myself. ill never give up the "beast", boats, sometimes the float,sometimes they dont.
 
I don't think you are missing anything unless the oil pressure pushed the plug back out a bit. You did say that it showed presure for a short time. That's why I suggested holding the plug tight by partially seating the cap on it. With the valve totally sealed, I would expect quite high oil pressure.
D
 
Anthony and Dave,
Was the relief valve cap off when the wood plug sealed as you assume it did? You had good oil pressure momentarily, but then it dropped off to zero. With the cap off, if the oil pressure pushed the wood plug out even a little, wouldn't oil come gushing out the pressure relief valve opening all over the garage floor?
What I am wondering is if there might be some blockage in the line that goes to the pressure gauge. Initial oil pressure reads, but then something blocks it up and the pressure gauge falls. How about hooking up a new line from the block and a new after market gauge (about $20 for a cheap gauge).
 
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