Reimax oilpump, fits like a sausage in a swimming pool

[K_arlstrom]

Since their answer regarding my issue has taken over a week, I feel that a heads up regarding reimax oil pump gear clearance is justified. Found some old threads with this issue, then some newer ones stating that it's fine, and went for the "cheap" solution.

This is the fitment of the uprated oil pump (over 0.45mm, got a 0.05 feeler gauge blade stacked beneath) on a brand new crank.

Let me know what your experience has been with Reimax or similar solutions!

Now, I'm waiting for a spline drive kit.. Don't do the same mistake as I did, the expensive solution will just cost even more 

(I lost oil pressure which led to bearing failure, and the crank needed a lot of work to be ok again. Someone, at some time, fitted a narrow nose crank in my late -93 R32. The oil pump chewed some small pieces of the bearing so it too had to be replaced or repaired.)

[K_arlstrom]

Shameless bump to see if it's possible to start the discussion. 

Got a reply today where they claim this is as intended, would you feel ok with this much play? 

[KiwiRS4T]

So have you measured a stock pump? What downside do you fear?

[K_arlstrom]

10 hours ago, KiwiRS4T said:

So have you measured a stock pump? What downside do you fear?

Not stock, no, but the N1 pump that's been in the last 8000 Km. N1 got somewhere just over 0.30mm but it still showing signs of wear on the edge where it usually breaks. I want to feel "safe" pushing the engine, and since the pump had to be replaced or upgraded, I thought "better safe than sorry" and bought the salespitch. The gear might be up to the task, but it just seems too much.

So, for all you who prefer thou to mm, reimax: ~18 thou and N1 ~12 thou.

Edited August 24, 2018 by K_arlstrom

[MrStabby]

I dont know anything about engine building, but if the reimax gear is made from a different material to the N1 gear, then it could have a different co-efficient of thermal expansion and therefore require a different clearance. That's just theory tho - I have no intuition on whether its a likely explanation in this case. Let us know when they get back to you.

[KiwiRS4T]

21 hours ago, K_arlstrom said:

Shameless bump to see if it's possible to start the discussion. 

Got a reply today where they claim this is as intended, would you feel ok with this much play? 

Well yes. It would be very easy for Reimax to make their gears with a smaller clearance so I assume they know what they are doing. You have reported that the length of the crank nose  was the problem last time ...not the amount of clearance.

[K_arlstrom]

On 8/25/2018 at 5:24 AM, MrStabby said:

...different co-efficient of thermal expansion...

Fairly similar from what I can find, not close enough to stop it from lashing back and forth. They state that it's normal, but they didn't want to give any recommended clearance or warranties, "If it works, it works, we got out money" is how I read their reply.

On 8/25/2018 at 8:54 AM, KiwiRS4T said:

Well yes. It would be very easy for Reimax to make their gears with a smaller clearance so I assume they know what they are doing. You have reported that the length of the crank nose  was the problem last time ...not the amount of clearance.

Old pump didn't break, but were visibly worn where it's reported to break. Since I'ts an engine out job, and the pump had bits of bearing in the cogs, I wanted a solid replacement to never have to think about it again.

Anyways, everyone who has read the thread seems to be ok with Reimax gears and the, IMHO, massive clearance. Keep an eye out for it at a bargain price on ebay ;)

[MrStabby]

On 9/5/2018 at 7:14 AM, K_arlstrom said:

Fairly similar from what I can find, not close enough to stop it from lashing back and forth. They state that it's normal, but they didn't want to give any recommended clearance or warranties, "If it works, it works, we got out money" is how I read their reply.

Well that's not cool.

What the factory clearance? On page EN-96 of the shop manual, it says "Measurement position 5 is the figure obtained by subtracting the housing flange outside diameter from the the inner gear inside diameter" and shows a micrometer being used on the inside of the inner gear. If "housing flange" is some weird engrish for the crank mating area, then the clearance is 0.045-0.091 mm (0.0018-0.0036 in)...

[KiwiRS4T]

1 hour ago, MrStabby said:

Well that's not cool.

What the factory clearance? On page EN-96 of the shop manual, it says "Measurement position 5 is the figure obtained by subtracting the housing flange outside diameter from the the inner gear inside diameter" and shows a micrometer being used on the inside of the inner gear. If "housing flange" is some weird engrish for the crank mating area, then the clearance is 0.045-0.091 mm (0.0018-0.0036 in)...

Well according to the above the Reimax is well within spec. The last thing you want is the pump seizing on the crank.

[K_arlstrom]

MrStabby, if you look at the next page you see where/how to measure "point 5"

Inner gear and housing flange clearance, 0.045·0.091

[NZ-GTT]

I used the Reimax gears and have had no trouble. They also had the large clearance I assume too that Reimax know what they are doing since they built the Clasonic GTR back in group A days. Is there evidence that the large clearance is a problem, I think it is a good thing for crank flex.