oil pump to distributor too tight, shredded my cam... (1 Viewer)

[ridefastflyfar]

This summer i pulled the 2F out of my 40, had everything machined for a rebuild, bought parts from the machine shop, and built it back up. When it came time to put the dizzy back in, it was TIGHT, (and yes, this is where I should've re-directed, but then there would be no story). I rotated the engine with a wrench, things all seemed to be fine, so in it went. Fast forward to trying to start, hear a funny squeaking noise, and no fire. Pull the cap, and the rotor isn't spinning. Distributor wouldn't come out without a pry bar, and my cam looked like this:

Pulled the cam, got a new cam, delved into the problem, and the oil pump was a really tight fit on the distributor which caused it to jam up and shear off my cam teeth. Used an old pump to get on the road with a new distributor (broke the old one getting it out), and went back to the parts guy. He said he hadn't seem anything like it, ordered another pump, and it's the same. I have 4 different distributors and two old oil pumps, all of which interchange. Both new pumps do not work with any distributor. The parts supplier is saying there isn't an issue, must be something I'm doing. Have I missed something here? There isn't a ream step I should be taking before installing a new oil pump, is there?

BTW, didn't find this via search, so maybe someone out there has seen it and can help.

 

[John Smith]

I'm sure you're beyond frustrated by this point. First we need to know which distributors you are using, along with oil pumps, and cams. Pictures please. I have seen older DUI dizzy gears get eaten by cams before.

 

[ridefastflyfar]

I can take more pictures when I'm back home, but until then, I'll start with descriptions:

"stock" rebuild, with a stock cam. gears matched old cam and the second new cam
distributor was the stock, '78 dizzy, replaced with an '86 2F. Also have on hand a couple from an '89.
oil pumps were both from the same guy, without a name on the box. I looked up the part number with him this morning, and his supplier just shows "oil pump, 2F".

I'm up and running using the old oil pump, but want to get a new one to swap in at my 1000 mile oil change.

Also, the dizzy gear is actually fine, but as you can see, my cam was the weak link.

 

[John Smith]

So it sounds like you have some bad after market oil pumps that are the issue. The stock oil pumps seem to last for the life of a 2F. You can flip the gears in the stock pump if they are worn.

 

[ridefastflyfar]

I think that's correct, but wanted to make sure I wasn't missing some step that others know but I don't.

The old pump that I'm using now is a stock Toyota one. Maybe I just leave the thing in there and watch my oil pressure over time. Felt a bit odd to put the used pump back in a fresh rebuild, but maybe that's not so bad.

 

[simps80]

Wow..I had the same exact problem!!
2f rebuild new melling cam..itm pump 76 distributor...never found anything on search..

Ruined cam distributor and pump getting it back apart.
http://www.risingsun4x4club.org/forum2/showpost.php?p=253162&postcount=160

Never figured it out new pump cam and distributor went back in fine.
I think some cams might be geared wrong..new cam was different brand

 

[ColonelMustardFJ40]

If you removed the oil pump support from the base of the block when you rebuilt you engine, then you may have an alignment issue between the oil pump and the distributor. I believe that at the factory this was line bored and should not be removed and replaced without careful alignment. I attached a picture for reference.

 

[LAMBCRUSHER]

^^^that. it can be realigned by loosening the mounting bolts, installing dizzy and snugging up bolts a bit and pulling then resetting the dizz at each step of snugging the bolts...pain in the rear. I now have a junk dizz, but was lucky to get things back to the way they should be. I ended up dropping the pan and beating the dizz up and out with a hammer and piece of bar...my cam survived, too bad about yours

 

[ridefastflyfar]

I did remove that mount block when i had things machined, so that may not have helped my situation. During the second installation, (when i put the old oil pump back in), I had a distributor in place and everything together before tightening those bolts to the block. I'll know next time for that!

It's still interesting to me that both the first oil pump and a replacement pump from ITM are too small on the bore for the dizzy drive. Those parts are all at the machine shop, awaiting the parts rep to come and see for himself. Next week there is a Melling pump coming in. When it gets here, i'll go in and take pictures in case anyone else finds themselves in a similar situation.

 

[ridefastflyfar]

Simps80-- looking a the date of your post on RisingSun, we were building around the same time. When did you buy your parts? I bought mine in late May/early June. Maybe there's a funny batch of the oil pumps out there.

 

[chato]

oh crap, I have a new melling cam and a new ITM pump about to be installed in a 2FE
anything that can be picked up on inspection after assembly (or prior to) aside from binding on rotation?
The distributor and pump appear to mate satisfactorily, the distributor is a 3fe

 

[ridefastflyfar]

Yeah, inspection is easy, and you should do both before and after oil pump installation. Before install, put the distributor in the oil pump and turn it. Mine wouldn't actually go down into the oil pump completely on the bad ones, so it was obvious there (on the second bad one, that is). If your distributor goes in fine, then you need to make sure the oil pump block is aligned with the distributor bore in the block, so assemble that loosely, drop in the distributor, make sure it's all turning without binding, then tighten it up. In retrospect I'd have made sure the oil pump block was aligned prior to cam install.

 

[chato]

thanks, yeah, the oil pump and distributor articulate just fine not installed.
and the check at assembly makes sense, I also removed the oil pump block so I'll make sure that it is good and straight. Still torn on whether to use the ITM pump, I also have two used factory pumps that I could inspect for wear as well. or just plunk down the $100 for an new aisin.

 

[ridefastflyfar]

It's probably just fine, since it freely moves. I ended up with a Melling, but only because I had two bad ITM's and it was easier to get than an Aisin.

 

[chato]

scrap that, found an Aisin for $70 shipped on Amazon.

 

[micruz60]

Is the ITM brand -not so good- china made quality?

 

[chato]

yeah, typical china quality, rough casting, the part that articulated with the oil pump block isn't nearly as polished as on the factory or aisin units. But I haven't opened it up so I don't know what the guts look like. it's probably fine, but with all that's gone into this rebuild, not worth chancing over $70.