T16 TURBO TIMING - DEFINITIVE ILLUSTRATIONS

MGJohn · Post by **MGJohn** » Fri Apr 22, 2005 12:45 am

Following on from my "28 and 29 What's the difference" thread, here's pictures showing correct location of Crankshaft and Camshaft Pulley Indexes when fitting a Timing Belt to the DOHC (Double Overhead Camshaft) T16 Turbo engine. It's essential that these indexes are all lined up correctly. However, as there are TWO location slots in BOTH Camshafts, this means that 2 x 2 = 4 so there are four possible location combinations...:

ONLY ONE IS CORRECT

The above illustration shows the crankshaft pulley index in the 9 O'Clock position. Then, pistons Nos. 1 and 4 will be at 90 degrees BEFORE TOP DEAD CENTRE and pistons Nos. 2 and 4 at 90 degrees AFTER TOP DEAD CENTRE. All four pistons will be at the same level in the cylinder bores. When 'timing' the engine prior to fitting the timing belt, that crankshaft index must be set like this.

The INLET CAMSHAFT PULLEY (on the left) and EXHAUST CAMSHAFT PULLEY (right) need to be in this position. However, it's not as simple as that because there are TWO slots on the camshaft pulleys- see next pictures - and the correct slot must be selected..

LHB10028 - EXHAUST PULLEY with its locking bolt removed to show that the slot marked 'EX' must be located over the roll pin.

Again with bolt removed, INLET PULLEY LHB10029 with the Roll Pin located in the slot marked 'IN'.

This is how they should look with the timing belt in place. However, before starting that engine, DOUBLE CHECK AGAIN that the index mark on the CRANKSHAFT PULLEY is still in that 9 O'Clock setting.

Pictures taken earlier today of the engine in my 1993 TomCat Turbo.

T16 Dave · Post by **T16 Dave** » Fri Apr 22, 2005 12:47 am

Sweet, well done John :thumbup:

A possible FAQ/Sticky?

Post by **IrishRover** » Fri Apr 22, 2005 1:14 am

Nice one John. I really appreciate that you take the time to demonstrate something in an easily understandable way and without assuming any great amount of existing knowledge yet at the same time not being condescending in any way.

Much respect to you.

TurboMG · Post by **TurboMG** » Fri Apr 22, 2005 4:15 pm

Arent those pulleys pointing the wrong way??? The IN arrow on the exhaust pulley should be pointing at the inlet cam and the EX arrow on the inlet pulley be pointing at the exhaust cam???

MGJohn · Post by **MGJohn** » Fri Apr 22, 2005 4:25 pm

TurboMG wrote:Arent those pulleys pointing the wrong way??? The IN arrow on the exhaust pulley should be pointing at the inlet cam and the EX arrow on the inlet pulley be pointing at the exhaust cam???

Hi Ian,

Could be .... If they are the 'wrong' way, I can recommend it because I've never owned or driven a bog standard T16 Turbo that runs better ...

To do that would mean rotating the Exhaust cam's pulley a further 180 degrees ... then the IN would become an NI .... I think.

Post by **Fordimus Prime** » Fri Apr 22, 2005 4:28 pm

This couldnt have come along at a better time- am replacing the head on my t16 next week.

Well done that man!

matt10328 · Post by **matt10328** » Fri Apr 22, 2005 5:55 pm

fook, that means my timing is 180 out, I'm pretty sure on mine the "inlet" on the exhaust cam is facing the inlet manifold, and the "exhaust" on the inlet cam is facing the exhaust manifold.

This is with the crank being No.1 piston at 90 degrees btdc, 9 oclock postion.

The writing on mine is also upside down, correct pulleys tho and correct roll pin position.

Mine does turn over without any problems, valves hitting etc, and does have good compression, but doesn't start although that I'm almost 100% certain isn't to do with timing, since I have a wiring problem with no spark. But once thats sorted then I guess I will c whether it starts and if not then that means :-(

turning the pulleys round 180 then the writing wud be the right way up and look identical to that in the pics.

And if ur car works fine and runs fine then the method u described above has to be correct........

this should be a sticky/faq defo.

cheers

Matt

xr4x4 · Post by **xr4x4** » Fri Apr 22, 2005 6:34 pm

geeza10328 wrote:The writing on mine is also upside down

yup....upside down isnt good.

geeza10328 wrote:this should be a sticky/faq defo.

i agree.....

fluke · Post by **fluke** » Fri Apr 22, 2005 7:16 pm

Top job there John.

Agree it should be a sticky.

Grant620 · Post by **Grant620** » Fri Apr 22, 2005 10:58 pm

Absolutely fantastic mate.
I've made it a sticky AND moved it to the FAQ section!
Cheers!

Grant620 · Post by **Grant620** » Thu Aug 17, 2006 9:59 pm

New link:
http://web2.a15171219.alturo-server.de/ ... imeing.pdf