1984 Porsche 928s Timing Belt Replacement


#1

I’m contemplating tackling the replacement of the timing belt, tensioners, water pump and drive belts. I’ve the factory manuals detailing the procedure but reading and doing are two different things. Anyone have any experience doing this with a 928 and its degree of difficulty and have any tips? I’m handy with automotive repair, I’ve done a timing belt change on my 85 VW Golf diesel but the Porsche appears more involved…and so does the cost of parts.


#2

By the way, there’s an indicator light on the instrument cluster that lights up and shows a middle finger when the timing belt breaks along with a flashing $$. Just kidding, thought I’d add a little levity here.


#3

You should find a Porsche forum, get to the 928 discussions, and ask around there. I know it’s complex/difficult from others whose opinion I respect. But I have no idea about the particulars.


#4

You misspelled Porsche, is is actually spelled Por$che,

May your banker have mercy on your soul!


#5

Never done a 928 but it appears to be a bit involved. Maybe this will help as a guide.

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

No matter the make of the car there is one bit of advice I can offer. Before ever starting an engine after a belt replacement step back, take a deep breath and mentally verify that all bolts are tight.
After that, rotate the engine through by hand at least 3 or 4 times and verify the timing marks are all aligned.

If you botch the job an illuminated flashing screw light will appear. This works in conjunction with the $$$$ light…
:slight_smile:


#6

Not to worry, do it wrong and you’ll have one of these:


#7

Thank you for all the responses and especially the info from ok4450. Yes, it’s certainly much more involved than a VW belt replacement. A mistake and I wind up with a nice coffee table, very funny! I’ll read through the procedure several times then decide if I want to undertake the job.


#8

I understand up to and including 1984 the 928 has a non-interference engine, 85 and beyond had the interference curse. Is this true? If so, if a timing belt breaks in a non-interference engine would I getaway with no engine or valve damage just a belt replacement?


#9

The Gates catalog indicates that all 928 engines are interference engines, which is consistent with comments from auto experts I trust. Who told you otherwise?
http://cdn603.ilcdn.net/files/20110223193902/gatesdocs/TimingBeltReplacementGuide.pdf


#10

I came across the info from the Pelican Parts 928 technical forum under the thread “Update: new Porsche guidelines for timing belt/water pump replacement intervals” initiated by m21sniper. Actually there’s mention throughout the forum that 928’s up to 1984 don’t have the interference engine. Perhaps Gates is just being cautious stating that it does. Need to 100% confirm if it does or doesn’t just for peace of mind.


#11

I’d trust Gates over a poster on a forum…oops…