[Racefiend]

I'm in a bind. I bought a new 7m pump to throw into my 7mgte. Of course one prob is redoing the pickup. However, ,due to the pumps different orientation, it does not clear the arp main studs. And even if it did, it looks like the crank counterweight will hit it, if not it would only have a fraction of an inch clearance. The 5m pump fits like a glove. I like the 7m pump cause its new. Would it be possible to transfer the guts from it into the 5m pump? Also how thick of a washer would I use to up the oil pressure, ,and what would that new pressure be?

TIA

Christian

 

[Racefiend]

OK, never mind. I took the two pumps apart and found that they shortened the pump body, ,and elongated the pump cover on the 7m. This allowed them to shorten the gears and have an exposed shaft to fit into a recess on the pump cover (now that it's taller and can have a recess). They must have done this to give better support to the shaft, for more longevity. So no, the innards are not interchangable.

I did notice that the parts/function of the two pumps are almost identical. I do not see any reason to switch to the 7m pump as they should perform identically. I will be using a 5m pump now. Way less hassle.

Christian

 

[Racefiend]

whoa, looks like we posted at the same time, Wade. Yea, thats pretty much what I came up with.

As far as the gears, I found the opposite to be true. The 7m pump had smaller gears and a deeper pump cover compared to the 5m I have. I don't know what year it is, though.

I already have the 85 pan (got it from autozone for only $55). I will be exchanging the 7m with a 5m hopefully. Unfortunately I've had it for about 1 year I'll find out tomorrow. I checked part numbers for the pumps for an 82 and an 85 and they are the same at the auto parts stores. Are you sure they're different?

Christian

 

[Racefiend]

Hey William,
At the end of the pump, near the pickup, there is a cylinder about the size of a battery sticking out of the pump. The spring is inside this cylinder. At the tip of the cylinder is a nut that holds the spring in with a hole in the center to relieve oil. You can put a washer between the spring and that nut.

As far as the discussion on the mk2 list, I remember that one. One of the members (cant remember who) said his dad is a machinist and they pulled both apart and measured everything and they were identical internally. You musta missed that one.

Christian

 

[Racefiend]

Well, I just sent back my new 7m pump for a 5m pump. They had the same part number for 82-86. We'll see what I get when it comes in.

Christian

 

[Racefiend]

3-4 psi!? I think there's more there than loose clearances. You may have something wrong with your pump. My mk3, with tired JDM rod knocking engine, puts out at least 10psi at idle when hot.

Christian

 

[Racefiend]

Well, I got my new oil pump in the mail yesterday. It's an application for 82-88 5mge. It looks exactly like the one I used to compare to the 7mgte unit (and found they were basically identical). I checked the clearance with my 85 pan and it had ~5mm clearance. Looks good and I'm going to use it. pre 85, post 85, i don't know, but it works.

Christian

 

[Racefiend]

well, i originally ordered a rebuilt 7m pump ($119) my cost from Topline. They didnt have one so they sent me a new one for same price. That wouldn't work so i replaced it for 5m. So 119 for brand new pump w/pickup. Prices went up since then I think. p/n OPTO19L

Christian

 

[Racefiend]

UHHHHHHHH....I hope you had a worn shaft or something. Cause I just put in a brand new 7m shaft and just got done torquing the head down on the (mega expensive) hks stopper gasket last night. I will have to try it cause I refuse to go through all that work/money again.

Christian

 

[Racefiend]

GREAT! Thanks for the reassurance :wink:

Christian