Manifolds and Risers questions-gctid374785

[Mikalkc]

After all the discussion of failing manifolds I broke down and looked closely at mine and decided new ones were needed. I have the Volvo BB225B (GM 305) installation and was able to find numerous sources for both manifolds and risers. Now that I have them I am curious how many have changed them with the engines in place in the boat. I have minimal clearance on the outside cylinder banks and would hate to snap a bolt since it would mean removing the engine to repair.ops The inboard sides are relatively accessable so I can use impact tools there. The outboards will have to be a long breaker bar and socket, the best known tools for snapping manifold bolts. Anyone have any other suggestions for removing the old bolts?:surr

[2850Bounty]

Warm the engines up before you attempt to crack the bolts loose. You can do the actual work once things cool back down.

The automotive version Anti-Sieze works well for exhaust manifold to cylinder head bolt threads.

.

[tonyiiiafl]

2850Bounty wrote:
Warm the engines up before you attempt to crack the bolts loose. You can do the actual work once things cool back down.

The automotive version Anti-Sieze works well for exhaust manifold to cylinder head bolt threads.

.

PLUS 10 on that. I also each year at the end of the season, break a bolt free and retighten. After 6 seasons, my manifold bolts came right out. Yes, I used originally automotive NEVER SEIZE on installation.

[Chief_Alen]

shoot the bolt heads with pb blaster. Wait and shoot them again. If you do snap one it just might not be that bad to get the rest out you can then heat the remaining piece and use a pipe wrench.

[2850Bounty]

I like PB Blaster as well as the next guy, but products like this can take up to weeks to enter the area where they need to get to.... in particular these exhaust manifold bolts.

This is why heating the engine up first, and allowing for a bit of expansion works well.

.