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Oil Pump Recommendation[s] for BJ8

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Patrick67BJ8

Patrick67BJ8

Obi Wan
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I'm rebuilding my engine and I need a recommendation for a New Oil Pump.

I have two old pumps and the cylinder walls where the gears go are scored.

Pressure was good before pulling the engine. About a third of the top of #6 piston disintegrated causing a loud clacking sound so I have to rebuild the engine due to cylinder wall damage(it has been bored 60 over). I had the gears of one pump CAD plated and baked to reduce the tolerances, but on the advice of a couple of local club members it was suggested that "if it were my engine I would get a new pump".
Thanks,
 
Bob_Spidell said:
Patrick67BJ8 said:
John Turney said:
FWIW, I agree with the local club members.
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Recommendations for a supplier?
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When I rebuild my BJ8's engine I'm going to use one of the Denis Welch 'high capacity,' per his recommendation. No experience with this part, but DW generally makes pretty good stuff:

https://www.bighealey.co.uk/category/catalogues/austin-healey/engines/3000-bottom-end?page=1
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I find it strange that a high-capacity pump, also more expensive, is recommended for a standard engine and the gear pump is recommended for race engines(non-standard).

I heard that there was problems with the high-capacity pumps when they first came out with them but I would assume that they have been corrected by now.
 
I believe it's because the 'high capacity' is similar to the earlier pumps, which are rotor types. The later BJ8 pump is a gear type. The rotor type puts out more oil at a higher pressure; from what I hear the earlier 6-cyl cars in general have higher oil pressure, esp. at idle. For a high-revving race engine the gear type puts out sufficient pressure with less parasitic loss; the rotor type may actually put out too much oil at too high a pressure and have greater parasitic loss (i.e. the pump uses more HP).
 
If I remember correctly, a number of years back there was a long discussion on the mailing list about the different pumps. At that time several people had experienced camshaft failures when using the rotor style pump, since it apparently puts a much higher load on the gears driving it, in a pulsed manner. The gear pumps run smoother.
 
I'm a fan of the "old" style rotor pump__they've never failed me, and I've been running one in my car for over thirty-four (>34) years now. Currently fitted with a 3000 (+.030" for 183 c.i. displacement), and of course, its original 2.6 engine that was fitted with the rotor pump at the factory.

I run my engine up to the redline at every opportunity, but it doesn't get much chance for sustained running at the redline. I have not had any problems with cam cears nor drive spindles.

Regardless of type, my recommendation is to have the oil pump internals polymer coated with a dry-film lubricant. Also pay attention to sharp edges on the internal passageways; smoothing these out with reduce pumping losses. For that matter, do everything that rotates or slides!

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Hello

Can anyone tell if there should be a bolt in in Randy Forbes oil pump picture.

If you look at the pump base , there is a stud and nut on right side. On left side there is a threaded hole. My eng was apart and i did not have the opportunity to look or photo this area. Iam guessing nothing goes in there.
Thanks
Phil
 
There is a reason that there was a changeover from the rotor style pump to a gear pump. The rotor pump put too much back pressure on the drive spindle, camshaft gear, timing chain and camshaft thrust plate. Early attempts to fix the problem by Austin were to put oil groves into the steel thrust plate and even used bronze thrust plates with oil grooves. The DW rotor pump is the same as the 100-6 oil pump that caused so many problems. Use a gear style pump....and beware of County brand. When you get one it will come with directions to "DO NOT OPEN THE PUMP" because the gears have "been carefully matched". Well, in a moment of desperation to get a new pump I ordered a County pump. Upon opening it to check it out, I discovered a huge void in the casting where the gears rotated. It would have ruined my fresh engine if I would have used it.

As for the stud - bolt question that Phil has about Randy's oil pump. There was at least one stud used by the factory in one of the holes. I don't recall off hand which one. It But since the concours people will never see it, I would not worry about it. Studs, nuts, bolts.... they all work just fine. Just don't over tighten.
 
The threaded hole next to the oil pump outlet flange (two studs/nuts at left) is where a steel tube goes to take the oil from the pressure relief valve down to the sump without spraying it all over the place inside. It seems a little unnecessary IMO. There is a second tube the same coming off the rearmost main cap to drain the oil from flinger. In theory.

Andy.
 
Thanks Richard, Andy, I was curious about the extra stud hole on the right side.
Phil
 
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