Porsche Enthusiasts Club Forum

Yes....you're right... ...I think if I'm honest, I have done so much to my car over the last two years....working on it every other day pretty much....this could be the last of the big jobs for a while and it is this bit I love. Just tinkering with it, finding out its challenges, researching, putting the questions out there and then getting a result. I fear that once the belts are done all that's left to do is just drive it.........well, apart from the headlining and the odd wheel/balance noise....

M

Normally the oil filter housing, or you got the balance shaft seals mixed up, there is 1mm internal diameter difference and they rotate in opposite directions, get it wrong and one leaks

Replaced the oil filter housing gasket and the OPRV valve seals, that side looks really dry and clean, just the centre front smack bang where the crankshaft is

Hopefully I got the balance shaft seals right checked, double checked and triple checked when fitting, hopefully will see where the leak is after removing the covers.

OK..took it for a final, final spin today. Lovely. A good 20 min blast. No balance belt slip. So all is good in the world.

Interestingly put the tool on the belt as soon as I got back and of course it registered it as super tight. Alu block has expanded a bit. Knowing how sensitive the tool is I imagine the temperature of the engine is critical to get accurate results.Reading my Arnnworx manual again it says "All adjustments are to be done on an engine that has cooled - warm to the touch is ideal. Shop and engine surface temperatures should be above 67F (19.4C)" - so I guess if you are colder or warmer than this it will effect the readings......

well...back on it.....

Tested the belt tensions last week with whizzy tool coming out of hibernation.....timing belt was on the slightly loose side of the scale but did not adjust it. Could still twist it 90 degrees.....Balance belt was showing too tight, so loosened it a wee bit to within spec on the tool which is where I can twist it 180 degrees in the middle span.

So, here's the thing...took it out today and the balance belt skipped a couple of teeth so clearly not on tight enough. The idler pulley is quite noisy and is on the way out so I'll get a new one of those and put some 1mm pre tension on the balance belt. The balance belt was always a bit noisy and guess the idler pulley hasn't helped....so a nice little project for next week.....thoughts?!

M

I would suggest that the gap between the belt and the roller is to big, it is only 1.5 mm,
Also you need to make sure that you have turned the bottom balance tensioner in the right direction
The balance is always far slacker than you would expect and should not jump, which shaft is jumping?

Its the lower balance shaft that is jumping.

The gaps are correct as per Clarks...though interestingly the whizzy tool says it should 'almost touch' the balance belt on the top of the idler pulley....so no '1mm pre load' which is what Clarks and others recommend.

I cranked it up tighter yesterday, so it is back to where it was before I fiddled with it and loosened it last week. I can still twist it by hand 180 degrees...and feels the same as before though with my whizzy tool it is saying it is too tight.

In any event I'll find out more next week when I drive it. I will need a new idler pulley though..........any recommendations on the www for one? I have found this one https://www.ebay.fr/itm/264715271045?_t ... 7Ciid%3A13 though it says it will not fit my '88 from the drop down menu even though it is the same part number..........

Frazerpart, can’t go wrong and probably cheaper than eBay

These “special tools” are designed to relieve the unsure of lots of folding stuff out of their wallet

180, plus or minus it’s a feel thing, you will know when it’s too tight as it will whine like a spoilt teenager
The gap between the balance shaft and the smooth idler above should stop it jumping, the tensioner to the left of the balance shaft must be tightened in the correct direction, anti clock I seem to remember

Been a good few weeks since I tightened it up a touch...all good and BB has not skipped. Guess my tool wants it looser than it should be.
Still have the upper belt cover off and no under bonnet insulation so all sounds a bit noisy and analogue down there...but guess that's the norm!

Happy summer motoring......

M