Cam belt change

[Brianem]

Hi all, new guy here. Jumped ship from old Jaguars to older Porsches. Heres today's question:

I just purchased an late 86 928 with 116k miles. The engines been wrecked (cam belt) once about 7 years and 8000 miles ago and rebuilt and seems like a good job. The seller gave a cam belt telling me to change it "before too long". From my position of ignorance, it seems to me that the cam belt probably broke because the water pump broke up, froze and the belt wore itself out running over a frozen pulley. If my thinking is correct, shouldn't I change the water pump when installing a new cam belt???

Many thanks in advance for your help

[19psi]

Yep, cheap insurance and that goes for any car with a water pump driven by a timing belt.

[robucop]

Originally Posted by 19psi

Yep, cheap insurance and that goes for any car with a water pump driven by a timing belt.

+1 on that, you may get away with not replacing the water pump due to the low mileage but why risk it?

[Danglerb]

Couple years ago I was mixed on changing the water pump, if it looked good, smooth bearing, maybe leave it alone. Now so much trouble with the rebuilt pumps that were used for years, and the improvements in the new pumps from Laso, I'm thinking put a good new pump in first chance you get.

[tmpusfugit]

I recently changed out a pump that had less than 5000 miles on it, but had been in the car for at least 10 years. The impeller was all "gooped up" with what appeared to be an outbreak of coral infestation, and there wrere signs of dripping under the impeller shaft. The rest of the cooling system was clean, radiator, hoses, front of block, etc, all clean. I have no idea why the water pump had the 2 problems but I am very glad I changed it (used a new Lasso). So, I would change the pump on your car as not chamging it and having a failure invites very expensive problems...namely bent valves and the like....time and the chemistry of the cooling system play a bigger role in the system than does miles...IMO

[harborman]

There is a detail procedure on Rennlist for doing the timing belt. Go down load it. Or just search "Timing Belt" on this site and you will find it. I was told to do the T belt every 5 years or 50K miles on a 32 valve engine. Use a New LASO water pump. You will get plenty of support here if you are doing it yourself.

[MPDano]

Your already there. Change it. Newer Laso Pumps have the plastic Impeller which is better for our cars.

I will always change out the WP on a TB job. On ANY car.

[dcrasta]

Originally Posted by tmpusfugit

but had been in the car for at least 10 years.

Originally Posted by tmpusfugit

signs of dripping under the impeller shaft.

Yes the signs of dripping is what you are looking for. Then again 10 year old parts sitting in water , pretty common that it would need replacement.

[dcrasta]

Originally Posted by MPDano

Your already there. Change it. Newer Laso Pumps have the plastic Impeller which is better for our cars.

I will always change out the WP on a TB job. On ANY car.

Kinda debatable . Plastic impeller can become lose on the shaft, but the result is cheaper than a metal impeller chewing the block for sure.

[MPDano]

Originally Posted by dcrasta

Kinda debatable . Plastic impeller can become lose on the shaft, but the result is cheaper than a metal impeller chewing the block for sure.

Exactamundo. Rather replace a defaulty Water Pump than an Engine Block. I can already hear sometimes the metal impeller chewing on my Euro. I bought the WP a few years back before the plastic impeller. Learn from those who made that mistake, like me.

[Danglerb]

I don't know if impellers coming loose with the new Laso will be an issue, but it looks like the best option short of the Guardian update.