E-type engine rebuild- oil pump and distributor drive issues

I’m finally making a bit of progress on my 3.8 e-type engine project, crank and pistons in, distributor drive in with issues as below, and have a question about the oil pump I got from Terry’s Jag parts. I’m trying to remember details, as this build has been delayed by a lot of things, but I believe the 4.2 pump has to be used, 3.8 unavailable, and there is a size difference of the pickup tubes on earlier 3.8 cars. The pump I got was modified with a brass sleeve for my early car and was supposed to be ready to bolt up. Of course, the early car o-rings in the seal kit are too small and I’ll be calling them about that tomorrow - must need the 4.2 size. What I’m a bit concerned about is the oversized bolt holes. Both the 3.8 and 4.2 are secured with dowel bolts, I assume to securely center the pump on the coupling from the drive. I think the castings are poor compared to the original, which has a machine fit. The current one is sloppy compared to that. My guess is that they are now all like that. Am I being too compulsive about this? Has anyone noticed this as a problem?

As to the dizzy drive, I had a loose distributor drive bushing. It just popped right out when I put the shaft in (shaft was a tiny bit snug). I fixed it by replacing the the #10-32 plug screw for the oil drilling with a longer allen bolt. It had to be shimmed just long enough to act as a set screw, but not distort the bushing. Anyone seen this problem? I’ve rebuilt several XK engines before, and have not seen this. I think my fix is adequate, but wondering what other experience is out there.

Hi Ron,. I was speaking to someone just the other day about the bolts for the oil pump as he too had the same issue. It was his suspicion that the pump may have been bored to fit metric bolts for an XJ6 and the imperial bolts on the 3.8 block are too small in diameter. He ended up making some sleeve bushes to take up the slack.
I cannot vouch for this as I also put a later model oil pump in my 3.8 block ( originally from a Mk10) and had no dramas bolts-wise.

Regards Jon.

there is a market here in the UK for good condition used original oil pumps. I had similar issues with a recent rebuild and having spoken to one of the more recognised parts guys (Ken Jenkins) he was quite vitriolic about the quality of some of the ‘new designs’ I bought a good used one and installed that. I have no issues with the engine performance oil pressure etc etc.

Ron My two cents like Jon, after my most recent rebuild of my 4.2 , USING ORIGINAL INTERNAL parts made life ALOT easier. Pistons and all were brand new but the small bits repro are terrible.
Even though mines not a3.8 we still used the original shaft.
I like new if NOS , the repro is just terrible.
Make sure when you return the shaft that its not 180 degrees out.

So, I had interesting discussions today with Engel Imports (Terry’s) - they having always been very responsive to me (no affiliation). They have not had reports of problems, but were happy to talk to Bill Terry for me about it, who asked for me to call him directly. I’ve enjoyed talking to him on several occasions when he has been most helpful on engine rebuild issues. Today, Bill says he has not noticed the problem that I spoke of, but the pump that he modifies is a made for Jaguar/Land Rover. Engel sells it for a bit more money, and I’m going to exchange the one they supplied me earlier, which I’m guessing is built on an offshore casting. Bill says that he carefully checks the drive dog for free motion when bolting up the pump, also backing up the engine a bit and rechecking. Bill says they would not have sized the pump I now have on metric bolts diameters. I think it’s just sloppy casting/machining.
It might take a bit of time to get the new pump as they show one or less in stock, so I will get back to the forum when I install it.

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I always checked to ensure the drive dog would slide loosely, with the pump bolted down.

Are you using the original bolts to fasten the pump to the main cap? The original bolts have oversized shanks and are specially machined for a close tolerance fit. A standard bolt will be loose.

Here are 3 original oil pump bolts and one good grade Holo-Krome socket head cap screw. All 3 oil pump bolts have precision ground shanks and mic out at 0.3100“ and are perfectly round to the extent I can measure. The Holo-Krome screw mics to 0.3080", plus or minus half a thou.

I think you’re correct, and you are prudent to be concerned. I sourced a NOS AE pump for my 3.8 last summer. Despite it being NOS, probably 80s, and having the correct factory dowel bolts, the pump could wobble sufficiently to completely bind the union between the pump and the dist drive.

If it was torqued up like that and driven, that union would have exploded in short order. It’s happened before to other people. What I did, as odd as this may sound, was to put heat shrink on the bolts then oil them a bit so the heat shrink wouldn’t tear when turning. I think I tried doing all three, but in that position it was causing a slight union bind. So I removed the heat shrink from one (or maybe even two) bolts.

After torquing and before lock tab setting, manipulate the union by hand. It must be able to move with no binding or resistance. If it doesn’t then loosen and try again.

Edit: I also suggest verifying that the pan fits easily over the new pump. Mine did not. The new pump was a fraction of an inch taller than the original and it collided with the pan baffle. It was necessary to file 1/16" off of the pier that the baffle bolts to. Then the pan sat fully flat even with no gasket.

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Thank you Erica. Those are great suggestions. I’ll see how the pump from Bill Terry works and let you know. I’m sure that I have checked this on past engines (it’s been awhile since my last rebuild, though), but I’ll be bumping up my scrutiny of that part from now on.

Yes, Mike, I’m using the original dowel bolts, but you make a good point. These are the same part number for the 3.8 and 4.2 engines, so theoretically should work for the modified 4.2 pumps. The problem seems to be with the casting/machining, not these bolts.

Reporting back on the oil pump issue. I received and test fit the new, new oil pump, and I have to say that the casting was no better than the previous. It was still uncomfortably sloppy around the dowel bolts, and, although I could have centered it, it didn’t make me happy. I tore down the original, and it was excellent inside, no evidence of cotter pin damage. I reassembled it and put it on the engine. I also note that the groove for the o-ring on the pick-up side was unusually broad, about the width of 2 o-rings. I think they are all like that now and it would be ok, but another reason to use the original.
I will return this pump to the supplier, who is very reputable and stands by their products. Seems that this is what you get these days. See my next posting about more substandard parts.

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Ron sorry your at that stage
I was there too , it doubles your time line to get things done but do it right now or pay later
Yes your paying and paying but it’s the new way of business .
In the end you will be happy like us!
Don’t put the shaft in 180 out our your distributor will have to be reclocked!

Thanks. Actually have been there and done that re-clocking, so it’s on my list!

Hi Ron I’m just starting on a rebuild of a 3.8l from a 1961ish Mk II. The car is long since gone, and the engine has been in indifferent storage for many many years. The oil pump in particular has a few divots from corrosion in one of the lobes that may be fixable. I see that SNG lists a variety of pumps for all sizes of Mk II motors.
I had a fitting problem with a new oil pump for my last 4.2l build. It was a reputable new British made pump. When fitted using the shouldered close tolerance bolts there was significant misalignment with the drive to the pump, so much so that I couldn’t fit the drive tube/collar. I wound up reinstalling the old pump which was not out of spec. The new pump was a “while you’re in there…” replacement.

I’ve removed a number of distributor bushings, and they have always been tight. You might consider having your bushing knurled at a machine shop which is a simple procedure and will expand the surface a bit and possibly give a tighter fit. The distributor bushing can’t come out - nowhere to go, but if it moves in the block and blocks off the oil port that lubricates it there might be problems.

The 3.8L oil pump is unavailable and has a smaller distribution pipe than the 4.2 which must be bushed down. I didn’t find either of the two I tried (neither was a cheap version) acceptable, but your results may vary, as they say.

My solution to the loose spigot bushing seemed fine, but required careful shimming of the setscrew to avoid distorting the bushing. There is a circumferential channel turned into the bushing which would prevent oil starvation of the shaft should the bushing rotate, but I agree that movement is undesirable. I attribute the loose bushing to the block having had pretty extensive welding by a cast iron specialist for freeze cracks.

Yeah I see what you mean. All the oil pumps SNG lists for the different varieties of the Mk II come down to one pump/one number, the same as the 4.2l E Type.

I have only done about ten engines but have never come across an out-of spec pump. They were mostly XJ engines, so no risk of split-pin ingestion, but still…

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Technically, only the suction side tubing is larger on the 4.2L pump. The discharge side is the same.

Hoburn-Eaton 4.2 pump on a 3.4L.

The Country pump (which I believe is the only one available), has mounting hole slop. As I indicated above, a NOS AE pump did also. But the problem was very easily solvable by putting a single layer of heat shrink on a bolt. It took up all the slop and squared it up. And it’s trapped inside the hole so it isn’t going anywhere. Ideally they’d make larger diameter bolt, and perhaps someone should offer them that feedback, but it’s really not that big of a deal, IMO.

I ran with a Country pump that had the same issue for 15 years and I didn’t even use the heat shrink trick. So long as you verify that the union moves without any binding at all, then it’s going to do its job fine. The problem is when people don’t check it. It’s possible that they’re deliberately designed to have a bit of play so it can be moved to align the union better.

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5 random oil pumps. The 3 on the left are 4.2L pumps and the 2 on the right are 3.4/3.8L pumps. The far left 4.2L pump is unique in that it caries the COUNTRY maker’s mark. It is the only one of the bunch to have metric cap screws retaining the cover. The two 3.4/3.8 pumps are Hoburn-Eaton.