OK to re-use timing gear bolt?

[Asmoday]

Is it OK to re-use the timing sprocket bolt that goes thru the IP gear and timing sprocket into the camshaft?

I picked a new one up at GM for a possible timing gear swap but after checking the bolt it was determined that it's Chinese made...

I got a new washer as well which is US made but I'm not sure if I should re-use the timing sprocket bolt as it has a fairly high torque spec...75 Ib.-ft. for a 10mm x 1.5 pitch bolt.

Opinions..?

 

[Iceman3005]

I do believe the TM says to replace the bolt, If it were me I would replace.

 

[319]

Seems like a lot of torque for a 10mm. Might want to verify that.

 

[doghead]

The general torque chart in the TM says 40 or 48 ft/lbs, depending on grade (9.8 or 10.9)

 

[Asmoday]

I did "verify that". That is why I'm asking the question. That torque spec is from the TM. And where in the TM does it actually say to replace the bolt? I could not find it?

I know what general torque specs are for metric bolts as I have been working with titanium hardware and anti-seize for years on my race bikes and was forced to pay very close attention to such things...

Hence...my question on this application...See the TM below...

 

[doghead]

I did see that also.

I don't have a good answer.

Are you using the bolt or an installer tool to reinstall it?

Maybe look at a civilian manual to see what they list.

 

[doghead]

The GM service manual says 200 ft/lbs.

 

[Asmoday]

doghead thanks for the reply...

I'm not sure that I will even need to do the gears yet. I'm just trying to get all my ducks in a row before I start the tear down today. If the timing chain in within spec I probably won't touch it.

I would be using a installer kit with bearing, washer etc. I'm not a big fan of using the bolts to press back on.

My only other related question on the gears is I will obviously have to remove the IP gear on the pump so I can get the timing cover off to reseal...

There are 3 bolts that hold that gear on and they are made with washers already on them . Their torque spec seems high as well at 30 ft/lbs....41nm.

NO one has these bolts in stock locally and I'm not in a position to wait a week. They have a integral washer on them which bring up the same question...

Can I reuse the 3 IP bolts that hold the gear onto the IP? I cannot find anywhere it says to replace them but again...30 ft/lbs sounds high for a 8mm / 1.25 pitch bolt...???

I wish I had a factory GM manual but I don't....

 

[73m819]

The GM service manual says 200 ft/lbs.

200 ft/lbs, sure not 200 in/lbs

 

[Asmoday]

Doghead....I think you misunderstood. I know the damper/crankshaft bolt is 200ft/lbs. and I do have a new one for that.

I'm talking about the bolt that goes thru the lower IP gear and camshaft timing sprocket into the Camshaft.....

as well as the 3 bolts that mount the upper IP gear to the injector pump.

The torque specs seem high on those bolts related to their dia. and pitch. and I don't see the TM saying to replace them.

I definitely will have to pull the IP gear off the injector pump and will be forced to reuse those since they are not available locally....

200in-lbs would only be 16.7 ft-lbs...that does not make sense...

 

[doghead]

I would reuse the 3 bolts.

 

[Asmoday]

Thanks doghead...

I found my old Chilton manual and the torque specs coincide for the most part. IP gears, mounting the pump etc.

On the camshaft bolt the Chilton manual says 65ft/lbs. / 88nm so the TM lists the camshaft timing sprocket bolt at 10 ft/lbs. more....not sure why...

Is there anything wrong with using a drop of blue Loctite on the 3 IP gear bolts when I put them back in for good measure?

 

[doghead]

I see no problem with that.