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Help...Leaking water pump after TB replacement

3409 Views 10 Replies 4 Participants Last post by  steevmac
Just replaced the timing belt and new components of kit on my ALH, buttoned everything back up, warmed the engine up to check the IP timing (got my timing right where I wanted at 58 :D), after several adjustments and restarts I notice the coolant (my fresh new coolant) level is low. OK I top that off attributing to air in the system, let her run about 5 more minutes and notice the level is down again, further examination is the new water pump leaking. I have removed everything to be able to get a visual on the water pump, with the ending running it appears to be leaking around the top of the casing. Is it common for the O ring on the pump to get pinched during installation? When installing I coated the seal with new G12. It did go in a bit difficult where I had to insert the WP bolts and walk it in, I would have preferred that I was able to push it in but no such luck which I attributed to just being a new seal. The pump is a new Graf metal impeller pump. As it was a bit difficult to get in I tried inserting the old pump which I was able to push in by hand, again I attribute that to the seal which was the original which had been in place and compressed since 2002. It looks like I should be able to pull the water pump without having to undo the new 1 time use motor mount bolts, does anyone have any tips for reusing the new Graf pump. I am wondering if the G12 may have caused the O ring to swell causing it to roll out of the slot during installation. If the seal looks intact when I get it out tomorrow I will try coating with grease rather then G12 to reinsert. Hopefully that is all it is and not a cracked pump housing. I know I will have to through the tension procedure again (aquire TDC, losen cam and IP pulleys), having been through that once on this ALH should be straight forward now.

Thanks in advance for any tips before I fly back into this in the morning.
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Water pump (new Graf) along with all of the timing belt components (rollers and tensioners) were replaced during the TB change. I suspect the O ring went in pinched, hope it is not destroyed where it cannot be reused else I will have to wait for another one. Question is...are the new water pumps with new seals that difficult to push in where they need to be walked in using their mounting bolts?
Pump is out, the O-ring is split. I have the old pump, the seal feels nice, flexible supple rubber, it is the original factory seal, car is a 2002 with 90K on it. Think there would be any issues using the O ring from the old pump?

A little bit of luck with the bolt, I purchased a bolt kit for my BEW (that timing belt job is coming up next) that uses the same stretch bolt for the body side of the motor mount. I know the stretch bolts are meant for 1 time use, in the application of the large roller since it is not critical like a head gasket is it possible to use them 2 times?

If no problems using the O ring from the old pump then I am good to continue today, else I will have to wait until Tuesday for the dealer to open.
Seal replaced, bolt replaced, all is well. Injection Timing 57 without having to adjust -:)
Now on to the BEW timing belt!

Before changing the timing belt on the ALH, I had noticed the engine surging about 100-200 RPM about every 30 seconds just normal driving, steady 55-60 MPH, does it whether the AC is on or off, also does it with the cruise control either engaged or disengaged. During the TB change I also changed the coolant temp sensor (Green one) so it is new. I have a VCDS, have run complete diagnostics and have zero codes. Any ideas what the surging could be? I had read on another site someone else having this same problem, It seems like the small surge when the transmission is ready to shift up to the next gear it surges a small amount before it changes however in this case, it is already in the top gear, I assume this is a lock up torque converter, could the converter be locking and un-locking, is there a test for that?
Surging Resolved

Changed the Transmission Fluid and filter, surging problem solved. You can only change what you can get to in the pan due to the cooler arranged on top of the Tranny. At about 2.5 qts in the pan, maybe another 1/2 that drops when the filter is pulled one may be able to get to ~ 3 qts. Ran mine for about 5 minutes then changed again (had a full case of synthetic) to ensure dilution of the old fluid trapped in the torque converter, cooler, galleries etc... Shifts sweet with no surging now.
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