Any overlap on timing belt and valve cover jobs?

[DougQ45]

Greetings all J owners. Just picked up a 1995 J30 with 155,000 miles in great cosmetic shape, however the former owner couldn't locate his service records, and "thinks" he might have had the timing belt replaced. The valve cover gaskets are also leaking.

I am planning on doing the timimg belt, tensioner, all rollers, water pump, cam seals, main oil seal, new radiator, B & M 70268 transmission cooler, & thermostat. I saw the post on timing belt replacement but no pictures are viewable. Does anyone know of a site that has pictures, as the service manual did not come with the car. Timing marks and alignment are unknown at this point. Perhaps a Chilton manual for the Maxima engine? Also, it looks as the the timing belt work is separate from the valve cover gaskets and no overlap exists, but I don't want to assume anything on a car I have never worked on before. Any suggestions would be appreciated. Doug

[yodawill2000]

Welcome to NICO !!
I luckily printed out the procedure when the pics were still up.
Helped greatly.
The J30 has the same engine as the N/A 300ZX
Not the Maxima.

To get to the Valve covers the Plenum must come off. Not fun !!
Theirs a link here somewhere to the J-30 Service manual.
It clearly shows the Timing marks.
Some one will post a link soon I'm sure.

[driverdriver]

T-belt procedure:

j30-timing-belt-replacement-procedure-t198122.html

J30 FSM:

http://www.nicoclub.com/FSM/J30/

[swimshark]

http://www.nicoclub.com/FSM/J30/1994_J30/em.pdf


start on page 14 and the rest tells you what to do with torque specs for everything.

i did mine about 5 years ago and am about to do it again in another 12,000 miles. make sure you get the timing belt covers and crank pulley off first. then with the crank bolt back in, spin the motor over using the crank bolt until all the cams and crank sprocket line up with the marks on the old timing belt. then go about removing the tensioner and everything else.

im doing mine every 60,000 with the way i drive my J30 just as they call for the 300zx. im not gonna wait every 105k.

[DougQ45]

So I stripped the front end down per the advice on this website (many thanks), and to my surprise found a Gates T251 timing belt in excellent condition. The old owner obviously replaced the timing belt, cam seals etc.... After installing the new radiator, transmission cooler, and filling her up with coolant, the J let out a shreiking noise upon start up that I assume is a quickly failing water pump?

To digress, the old owner cracked the radiator at the top tank and drove home (said didn't overheat) where he parked the car before selling it to me. However when I started the car in his driveway with a radiator full of tapwater, there was no sound from the water pump at all. (Had the car towed to my house after purchase)

After the repair and adjusting the tension on the alternator/water pump pulley, I could not get the squeel to go away...although it became somewhat quiet when the belt was so loose the alternator light was on! So back to square #1 so to speak. Afer reading numerous posts on the J water pump, they have been known to shear/break and cause a significant amount of damage, which I would like to avoid on the new radiator with 0 miles on it. I can only guess the bearings are shot on the water pump due to the dry run, and its time to replace the pump. Any thoughts on how tough the pumps are, and should I tinker with the belt tension some more? Should I run the engine for 5 minutes and let the thermostat open thereby providing lubricant to the bearings? Or just bite the bullet and replace the water pump?

[swimshark]

is it coming from the water pump itself or the belt? try belt dressing and maybe a lubricant on the water pump like wd40. it could also be your ac compressor belt. ive only had screeching noise come when i had ac on when i started the car. i have also had a water pump fail on me when i had my timing belt done at a shop on another J30. they used an off brand type and it sheared the pump. if you stay with the oem pumps this will not be an issue.

let it start up and run for a bit.

[DougQ45]

Thanks. The belt dressing and tension adjustment solved the squeeling belt. But when I ran the car for 10 minutes noticed a puddle underneath the motor, and went underneath to see fresh coolant dripping from the bottom of the crankshat pulley area. Guess it is a new water pump, thermostat, and the 1 inch water hoses which are prone to leak. Nothing like wasting 5 hours on a Saturday to have to repeat the whole thing over the next weekend. At least the labor is cheap. At least the car runs very well and is very smooth on the freeway.

[yodawill2000]

It goes much faster the second time, and third time, and ,, well you get the picture.
I would look for the source before pulling the water pump.
As you said the two short hoses are probably the source.
A good pair of sturdy needle nose pliers can get to the rear clamps.

Drain out that Tap water asap !!!
Only distilled water and A/F.
Also, the belts on the J have to be tighter than any other car Ive ever owned.

[swimshark]

it could be the short coolant pipes if a clamp isnt fully seated. also how much rtv did you put on with the water pump? i had an issue where i didnt have enough rtv and it was leaking on me.

[DougQ45]

How does the temp sensor which is covered by a black rubber sheath on the coolant inlet/outlet pipe get disconnected? I have tried pulling straight up, twisting it, and looking for a retainer clip and have not had any luck. Don't care to break it in haste. The yellow temp sendor I can figure out. Thanks.

[swimshark]

usually you just pinch it and it should pop off