Preparaing for my first timing belt/water pump job

[jefflamonica]

I just bought an 84 944 with 56K miles. For peace of mind, I know I have to change the water pump, timing belt and balance belt (among other things). I'm trying to figure out the correct parts, but one guy says I won't know until I get into it and can see whether it has an upgraded water pump. That determines which pump I buy and which belt-and-roller kit to buy. I'd really like to have all the parts together when starting the job. Is there another way to know? Cross-check against VIN or something?

Also, I'm assuming this is a good time to change the thermostat and gasket too.

Thanks in advance for your wisdom.

[flash75]

Check clarks-garage for water pump information. Look for water pump replacement under cooling system.

Clark's Garage Home Page

Clifton

[starryknite]

I was in the same situation when I got my car. I was all worried when I was having it done for the first time if it was updated or not. In the end, I ordered all the parts as if it was an order style from Pelican.

Go here for a list of what to buy: Water Pump Information and Replacement

Also, if you can see the block off plate, then you know it has been updated.
Picture here:




I stole the picture from http://forums.pelicanparts.com/porsche-924-944-968-technical-forum/379156-can-anyone-help-me-please.html

[Bradical]

Block off plate is a dead giveaway for sure.

BUY A FLYWHEEL LOCK! Setting and locking your engine at TDC is crucial. Also, the six 10mm bolts that hold the radiator fans in place are easier to remove than getting all of your rollers torqued properly with the fans installed.

Replace the rollers while you are in there too, any job worth doing is worth doing right and these are definite wear items. Its not worth putting new belts and a new pump and tensioning it up properly with junk rollers, gambling on $100 worth of rollers/tensioners against a $2000 valve job is pretty silly. Seals are up to you, easy to do while you are in there now...

[argiopeweb]

Swapping in a used head is cheaper than rebuilding one ($500-$700 last time I heard an estimate), and $2000 is really a worst case machining + WYIT cost. No need to scare people unnecessarily.

Agreed regarding everything else though. It's quite difficult (though not impossible, if you massacre the rear rear timing cover) to do the water pump without removing the crank pulley, and that's a job for a flywheel lock. Bruce Arnn of Arnnworx sells a very affordable one. Do yourself a favor and pick up his pin wrench while you're there. It's a bit pricey, but I was much happier doing this job with his hefty wrench than with the wimpy one I fabricated.

Fans are worth taking out, and, if you have to pull the crank pulley, they have to come out. Clearance on the radiator is exceptionally low when you put a gear puller in there, so it may be worth pulling the radiator as well if you don't want to bung it up. Also a good excuse to check its integrity/give it a good cleaning. YMMV.

Agreed with rollers & seals. Again, a bit pricey to do them all, but well worth the time and effort. Pulling everything apart twice is a pain.

Make sure the water pump mating surfaces are exceptionally clean when you put in the new gasket. I made the mistake earlier in the year of not properly cleaning mine and quickly developed a leak (necessitating doing it all over again). I now have aerograde Hylomar on both sides of the gasket to ensure I never have to do involuntarily do that job again (no pulley to go bad on mine), though there is a segment of the community that swears by dry gaskets. YMMV.

Don't forget to take detailed pictures of all steps. Minor details (like which side of the crank pulley faces the block, BTDT) can make big differences.

Feel free to PM if I can answer any questions. I've done it twice this year, so the details are still fresh in my mind.

[fiily]

Zim's has great prices on new water pumps and the timing belt kit. Do yourself the favor and replace the front seals while there, $160 for the races,oil seals, mylar seals, and the oil pump drive gear and no leaks out front for another 50-60K miles.Products > 924, 944 & 968 Parts > Cooling System > Water Pump

[jefflamonica]

Thank you all for your advice. I'll likely purchase the Arnnworx "maxi" kit with all the goodies, including (among other things) the pin wrench and flywheel lock mentioned above. I do plan on replacing the rollers and cogs. Thanks also for the tips about cooling fan removal. You guys, and this forum, are priceless. I actually pick the car up on Sunday. Then I'll see which water pump is currently installed and order appropriate parts. Just out of curiosity, is anyone on here near central Alabama?

[jefflamonica]

And one other quick question: What do you guys recommend as the replacement interval for the water pump? Every other timing belt change, for example?

[starryknite]

A lot of people recommend changing the belts every 30,000 miles and to change the water pump every other timing belt change.

[CHICKS]

I replace the WP when its bad.

[PorscheChef]

fiily is right- Zims is the best for the water pump. I only do everything if I plan to flip (sell) the car. I'm with CHICKS about the water pump though. I always replace the timing belt as soon as I get the car, the other stuff as needed. Everything can be done in less than three hours once you know how to do it, so it really isn't hard to go back in later if something needs attention. If it isn't leaking oil, I won't replace the seals and races until one starts to leak, then I'll do them all. If I'm keeping the car, at least for a while, I also go with Kevlar timing belts. About $125 versus $18 but I've never read where anyone has regreted using one.

[jefflamonica]

Thanks for the insights, Chef, et al! Trailering her home on Sunday. Then I get to see which water pump is currently on the car so I can order appropriate parts and the tools from Arnnworx. I'll keep y'all posted. Have a Merry Christmas!

[JonA]

Front end shaft seals like to leak. If there is oil anywhere around there, that is likely where it is coming from.
I have the front my engine apart now. I removed the radiator also as the lower balance shaft seal is being replaced. Makes it a lot easier. Also it was an opportunity to take a hard look at all the hoses and replace the two that were still original.

Jon

[M. Murphy]

JonA is correct, the front crank or front main seal is very likely to be the first leaking culprit. Make certain to get the oil pump drive gear, front main seal (correct size) and O O ring. Follow the installation instructions to the letter. If the main seal is installed right it work fine, if not it leaks.
Here's something that impacted my experience, the key on the front of my crankshaft was a feather key not the woodruff that most people talk about.
You can recognize a feather key quite readily by the radius ends. Don't even try to pry or pull this thing out, that will be a waste of time. Get yourself a source of compressed air, a 1/4" Air Angle Die Grinder, model 32046 from Harbor Freight. The bit is a 1/4" drive 1/8" diameter carbide burr. SGS #12725. Carefully grind out one side of the key until it can be remove with side cutters. If it is a woodruff key it should rock right out of the slot. These feather keys are a tight interference fit, essentially they become welded in place(my opinion).

[fiily]

Originally Posted by M. Murphy

JonA is correct, the front crank or front main seal is very likely to be the first leaking culprit. Make certain to get the oil pump drive gear, front main seal (correct size) and O O ring. Follow the installation instructions to the letter. If the main seal is installed right it work fine, if not it leaks.
Here's something that impacted my experience, the key on the front of my crankshaft was a feather key not the woodruff that most people talk about.
You can recognize a feather key quite readily by the radius ends. Don't even try to pry or pull this thing out, that will be a waste of time. Get yourself a source of compressed air, a 1/4" Air Angle Die Grinder, model 32046 from Harbor Freight. The bit is a 1/4" drive 1/8" diameter carbide burr. SGS #12725. Carefully grind out one side of the key until it can be remove with side cutters. If it is a woodruff key it should rock right out of the slot. These feather keys are a tight interference fit, essentially they become welded in place(my opinion).

I remember using the whole 16oz bottle of PB Blaster to remove all of the rusted nuts, bolts, gears, pulley's, woodruf/feather key when I did my front end reseal, belts and wp.

It was a mess from all of the oil leakage and then PB Blaster on top of it all. The mrs. wasn't pleased with the mess it made on the garage floor.