changing jackshaft

[GRMPer]

again with the stupid (for Saab nuts) questions...

the 'new' engine/tranny has the later (worse) drive gear on the distributor. How much of a pain is it to swap that if I've got the engine out already. any tricks to making it go smoother?

[Luke]

With the engine out its not that hard. Just follow instructions in the book. A local mechanic used to hole saw the firewall and pull them out that way too... sounds like a pain in the arse.

[Geoff]

You need a complete matched set of the earlier stuff (maybe you have that in the existing engine?). Remove the main pulley/harmonic balancer and the timing cover from the end of the engine. Remove the sprocket from the jackshaft and remove the timing chain. Remove the 3 allen key bolts that hold the plate that holds the jack shaft in. Remove the jack shaft. Remove the distributor and drive the tension pins out and replace the gear. Use a water pump puller to remove the water pump. Rebuild the water pump using the earlier shaft. Install the distributor and waterpump (using the special tool). Install the jack shaft. The rest is pretty much reverse of removal except you need to reset your timing chain tensioner.

I think that's it. I may have forgotten some details though

[airsweden]

I just did all of that to Big Zed in the fall. Good luck getting the timing cover off without killing the head gasket. I saw Seth take the cover off of an H motor a few times with out breaking it a while back but it was a new gasket. Mine was old and I wasn't as lucky but at least now I know I have a good HG. I recall there being some pain in the arse issue with my tentioner as well. Also If you can find good guides ahead if time it it could help, you may find you need them when you get it all apart.

[Jordan]

The scarcity of timing guides is becoming more of an issue than anything else on the b-motor. If you come across a good pair hold on to them.

Sounds like a PITA...wouldn't it be easier to just pull the motor?

[Geoff]

When I mess up the head gasket in that area I usually dope it up with Loctite 518. I figure the head gasket isn't under extreme pressures from compression in that area. I use 518 there (and everywhere on B engines) to ensure a good seal even if I don't mess up the head gasket.

[99Super]

again with the stupid (for Saab nuts) questions...

the 'new' engine/tranny has the later (worse) drive gear on the distributor. How much of a pain is it to swap that if I've got the engine out already. any tricks to making it go smoother?

Wait a second, just what are you trying to do? I may be missing some older posts, but just swapping the distibutor gear is easy. Pull the dist, punch out the roll pin (PITA), swap gear, replace.
However, you may run into a problem securing the dist (i.e., a 78 dist on a 76 block or vv...)
If you are updating the entire system to the 8-cog, then you pull the jackshaft LAST and install it FIRST. I don't think you can pull it if the WP and Dist are still in place.

john

[GRMPer]

I need (or should) backdate the jackshaft/wp/distributor to the earlier style on an engine this currently out of the car, so I was just asking for a rundown on the process. thanks!

[99Super]

Do you have all the bits you need? I'm dumping a bunch of my B-motor stuff and may still have a coarse set laying around...

[GRMPer]

well, I'd like to get another set so I don't cannibalize a good motor that I have....email me...per at grassrootsmotorsports.com

[Geoff]

I'm pretty sure I've pulled the jack shaft before pulling the waterpump. This prevented any fears that the water pump would be damaged pulling it past the jack shaft (when both had to come out anyway).

And I'm pretty sure I put the shaft in after I put the water pump back in for the same reason...

Someone correct me if I'm wrong, it's been a few years.

[99Super]

I have no way to prove you didn't, so I guess I have to believe you!

[DeLorean]

A local mechanic used to hole saw the firewall and pull them out that way too...

That sounds like a "Bill Moser" to me