MainePorsche

Kevin,
Just a little aside if you are going to check the tension yourself as a first timer. You will have to have the car securely raised. 6 ton floor stands x 4. Good low sitting jack. I recommend Porken liftbars for future work (http://liftbars.com/).
Once raised drain coolant from radiator. When replacing drain plug minimal torque (this Tech site has torques you should have https://docs.google.com/file/d/0BzC7...jI3/edit?pli=1), I believe 1.5Nm. You will need at 27mm 1/4 in. driver to rotate the crankshaft CLOCKWISE to TDC 0 deg. You WILL rotate crank two times past 0 deg. to TDC. You will measure tension at TDC.
Have fun.

Jim Devine

For just checking tension this should help:

http://members.rennlist.com/v1uhoh/checking.htm

For changing the belt/ water pump etc:

http://dwaynesgarage.norcal928.org/1987 Timing Bel

kevin2012

Thanks for your advices. I will have to wait for my belt tension tool arrives before I can check the belt tension. I had purchased the tool from 928 international today. Eager to check the belt tension and the warning light wire.

stealth

It is expected that the belt tension will need to be checked somewhere around 1500 miles after replacement, and it is expected that the tension will be reduced due to belt stretch. The dealer probably tensioned the belt to the center of the spec, whereas with a new belt, they should've made it tighter to account for this stretch. So, this doesn't sound like anything extraordinary so far-- hopefully you get the tool soon, adjust the tension per the writeups, and get to enjoy it without worry!

SteveG

You do not have to lift the car and You DO NOT have to drain coolant to check tension. If it is time to change coolant, this is a good time and it makes more room. You may want to remove the fans for ease of access, but you do not need to drain the coolant. The socket should be a deep 27 mm socket and it will require 1/2" drive or the metric equivalent of a 1/2" drive. I expect a 1/4 drive will twist off unless you remove all the plugs.

M. Requin

All of what SteveG said, and you shouldn't overtighten the belt to accommodate future stretch, this can cause problems. Set it correctly and reset it correctly.

kevin2012

Thanks everyone information. I suddenly know a lot about my 928 in few days. Power of the forum!! I think I know better than my mechanic.

Since I am waiting for the t-belt tension tool to come. I am playing with my car by fixing up some other things in the interior and eletrically.

Also, I had checked the t-belt warning wire coming out from the cam cover when the engine is not running. it seems to have a good earth.

Cheers.

Bill Ball

I have one buddy locally who was having intermittent warnings despite verified good belt tension. He found two faults. First, the tensioner warning wire was loose on the spade behind the cover on the top of the tensioner arm. He fixed that and the problem was resolved for a couple of years. Recently, it began happening again. This time he found the ground running from the spade down the tensioner arm had broken. The original ground there is a flat band of brass with a tendency to fracture. This should be updated to the mutlistrand wire type.

Hilton

Kevin - two links youi'll find helpful:

http://www.2010.cannell.co.uk/manual...s_porsche.html

And also the "Timing Belt" section of this page:

http://members.rennlist.com/pirtle/svc.html

As John SPeake notes above - there's a 3-minute delay before the warning system will report low belt tension, unless the warning system itself has failed.

The usual culprit is the either a break in the wire from the nose of the tensioner to the little brass angle piece, or the connector from the timing belt cover coming off the little brass angle seen at the top of the green loop in my picture.

As Bill notes above - the wire is sometimes a flat copper bridge which is prone to breaking - although my hazy memory says that was only used until 87 or 88, and that 89 onwards has the wire.

kevin2012

Just some recent update, the timing belt and gear look good. The belt is way too loose. The tensioner is dry, after I had added oil in the tensioner, the belt loose some more. So I guess the oil is necessary to lube the tensioner inside to make it function correctly. I adjusted the belt tension by using the belt tension tool and nomore warning light since then.
Thks.

WallyP

Kevin,

Congratulations! You appear to be well on your way to becoming knowledgeable and competent in maintaining your 928.

kevin2012

I purchased this 928 in May 2012. Only in about 2 months time, I had done the followings:

-adjusted the T-belt tension
-added oil in the tensioner
-ordered the carpet set from Garage 9 and had changed the whole car carpet
-fixed the leaking front automatic fluild hose
-fixed the leaking power steering hose
-fixed the headlight fine adjustment motor.
-changed all speakers and installed amp and subwoofer
-fixed a vaccum leak in the AC control panel
-connected the discounted wire of the idle stabling valve
-coolant and automatic fluid changed
-installed a keyless entry system and rear parking cam
-etc.

Upcoming
-install a rear spacer
-change the rear axle oil
-spark plugs change
-..............

Thanks for everyone and the forum to provide me advices and endless information. Without it, I will not be able to know my car this well. Now the car starts, idles and runs great. Gald to see that my car is getting better everyday. Working on the 928 is tough but very rewardable and fun. Hope I can up keep this youngtimer for a long time to come. Cheers.

PorKen

3 minute delay on startup. Immediate thereafter.