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850 timing belt...marks don't line up!Help!

'94 850 no turbo, 68,000miles

I recently purchased the car, and am replacing the timing belt. Presumably no one has ever done this on this car before, based on milage.

I've got the crank timing mark lined up, correctly. I've triple checked, had others look for that tiny little mark on the sprocket, and we all agree, that 'valley' in the sprocket with the mark is lined up with the raised pointer / rib on the block.

Both cams, however, have the tooth with the mark on them about one tooth to the left of the V notch in the cover. Both Volvospeed.com's instructions and the Haynes manual say these teeth should be lined up with the V notch.I've turned the crank clockwise several revolutions, just to double check, and each time I end up with the same thing.

Keep in mind, I've driven any other 850, so I don't know what the performance is supposed to be, but I felt the car ran well, and performed decently, so I am reluctant to put the marks in what the manual shows as correct.

What should I do? Asseb]mble it the was it is now, or as the manual says it should be?

Ron/Champ 6

1963 8E5 Champ (Champ 6) 1962 Lark Daytona Convertible (Boomerang) 1992 VW Passat (Taxi) 1995 VW Passat (Vanilla..yuk)
Reply to
Ron /Champ 6
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I personally would do it as the book says. As a check that you have the crank in the right spot, look at the roll pin hole on the crank pulley; it should be exactly at 12 o'clock position. If it isn't, set the crank pulley to 12 o'clock, and recheck the marks on the cam pulleys; do they now line up? If so, you are not setting the crank to the right spot.

Reply to
Jeff W

I had this whan I replaced mine. The problem is that the marks are supposed to line up when the non-tensioner (front) half of the belt is at full tension. It's impossible to pull the belt tight enough to do this. You end up meshing the belt around the crankshaft with one tooth of slack in the front side of the belt.

The solution was to rotate the crank about 1 tooth CCW (backward) and mesh the belt there. After installing and releasing the tensioner, the initial CW rotation fo the crank pulley took up the slack on the front side of the belt and everything aligned perfectly.

To reply, please remove one letter from each side of "@" Spammers are VERMIN. Please kill them all.

Reply to
Doug Warner

Thanks both Doug and Jeff.

The car sits in the garage awaiting the collective wisdom of this NG.

1) It probably has never had the belt off. 2) It ran fine, easy to start, ran smooth, decent power and milage. 3) It was one tooth off 4) Why was it one tooth off?

How much difference in drivability would there be if it truly were 1 tooth retarded on both intake and exhaust?

Ron/Champ 6

1963 8E5 Champ (Champ 6) 1962 Lark Daytona Convertible (Boomerang) 1992 VW Passat (Taxi) 1995 VW Passat (Vanilla..yuk)
Reply to
Ron /Champ 6

I know that on a single cam 240 Turbo having the belt one tooth off made it run like complete crap, I forget which way it was off, but the car had no power until boost, pedal to the floor in 1st gear it would crawl along for 3 or 4 seconds then take off like a rocket.

Reply to
James Sweet

On the other hand, the carburetted version of that same engine ran OK with the cam advanced or retarded one tooth. Advanced made about 30% worse mileage and slightly better torque through the whole range. Retarded made about 10% better mileage, but poor torque except between about 2500-4000rpm.

Reply to
Jim Carriere

In article , snipped-for-privacy@att.net by Ron /Champ 6 dropped his wrench, scratched his head and mumbled,

When the motor is initially setup at the factory, there is a jig in place across the rear of the cam shafts that holds them in position. After the belt is installed a mark is scribed on the cam gears to align with the notch in the cover. When doing a service replacement, the marks never line up exactly with the V notch. My experience ia that the scribe marks more closely align with the upper tip of the gaging cover section rather than the V. As a precaution, I generally mark everything prior to disassembly.

Bob

Reply to
volvowrench

Thanks Bob,

Maybe somone was in this engine before, because the cams are definitely 1 tooth retarded. I set it up per the manual tonight, and though I haven't driven it yet, it starts, idles, and revs well. We shall see tomorrow how it drives. The belt I took off has no markings of any kind...would the original be marked in any way?

Ron/Champ 6

1963 8E5 Champ (Champ 6) 1962 Lark Daytona Convertible (Boomerang) 1992 VW Passat (Taxi) 1995 VW Passat (Vanilla..yuk)
Reply to
Ron /Champ 6

Finished up all the repairs today, and took the car out for a spin. I set the timing per the manual.

Even though the car ran well before, it does have far more power and generally runs even better! The only mystery now is why both cams were one tooth retarded, apparently since new!

Thanks for everyone's help

Ron/Champ 6

1963 8E5 Champ (Champ 6) 1962 Lark Daytona Convertible (Boomerang) 1995 VW Passat (Vanilla..yuk) 1994 Volvo 850 (Tilley)
Reply to
Ron /Champ 6

All that ends well ....

I wonder if the belt jumped one tooth in use. That can happen if the belt stretches or the tensioner isn't working correctly.

John

Reply to
John Horner

The only correct way to correctly line up the camshafts is a special tool from Volvo that locks the cams in the rear (only fits one way) the camshaft gears have elongated holes in them if the camshafts were off by more then one tooth you run in to a problem

Reply to
G Klein

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