4AGE Water Pump Differences

**banana_socks** · 02-11-2010, 06:09 PM

Hey guys,
Recently pulled my engine to do a bit of work (AE92), including changing the water pump. I bought a replacement off ebay (maybe my first mistake) and I'm having a couple of problems. The pump was not identical to what was on the engine. There's an unused bolt hole, and I have to grind down part of the rib to clear the timing cover. No big deal, however now I've found out the pulley won't bolt on as they have different PCDs.

The original was ~55mm, the replacement ~50mm. Both pumps are the same height, which means it should be a FWD pump. Also theoretically the pulley will be in an identical position.

So the questions. Whats the chances of me modifying the stock pulley? Was thinking of either slotting the original holes slightly, or drilling new ones offset. Am I going to screw the balance doing this by hand?

What's the PCD meant to be? If its easy to get an aftermarket pulley with the correct PCD and offset it could solve my problems.

**dangdang** · 02-11-2010, 08:33 PM

Originally Posted by banana_socks

I bought a replacement off ebay (maybe my first mistake)

Me thinks so, if you have to modify everything around the pump wouldn't it be easier to get one that fits?

What brand is it Socks?

A Japanese made GMB one that I know fits as I have them on three of my Rollas can be had for between $80 and $120.

**banana_socks** · 02-11-2010, 08:53 PM

It was listed as a GMB water pump made in Japan, so 'theoretically' it should be of decent quality. Just seems to me like it might be for a different variation of the 4AGE. According to this site confirms it should be a FWD as the height is identical. My pulley also looks the same as the FWD on the site, however it doesn't specify if there is a different PCD between pumps.

I would probably rather buy a new pulley to suit than another water pump.

**dangdang** · 02-11-2010, 09:07 PM

Originally Posted by banana_socks

Just seems to me like it might be for a different variation of the 4AGE.

Hmm strange, as far as I know they should all have the same pcd, so even if it was a different variation the pulley should have fit.

**beerhead** · 02-11-2010, 10:41 PM

Will be 4AFE pump, a mate of mine had the same problem recently

**dangdang** · 02-11-2010, 11:01 PM

You could try a 4afe pulley then socks. Hopefully the offset and width/ribs are correct.

**beerhead** · 03-11-2010, 12:36 AM

I think for $20 at an engineering mob he had his underdrive pulley redrilled, but I bet the 4AFE pulley will work

**banana_socks** · 07-11-2010, 06:57 PM

Just thought I'd update this. Went to the wreckers in search of a 4AFE pulley, but didn't find anything that would work. There was a bunch of 4AFCs, and one 4AFE, but all had power steering, which runs the pump off a second row on the water pump pulley. Also the offset is different, so I doubt a single row would work anyway.

Decided to have a go at redrilling my current pulley. Knocked up a CAD sketch for reference and glued it to the face using the current holes to align it. Seems to be pretty dead on, but the real test will come when its running. Worst case the harmonics kill the pump, and I replace it with a genuine one.