Cleaning an engine with Seafoam, and the Amsoil sounds similar, is a good idea according to some and useless according to others, and some cite a risk of hydrostatic lock-up. Personally, I’m a believer. But, it’s not going to do much for exhaust valves, unless you do it with the car suspended upside-down.
MVS Moderator JDS60R
I’ve been using Amsoil products for almost 20 years now. I don’t like the power foam. Seems like diesel fuel in foam suspension. Doesn’t clean much.
Try the Amsoil PI fuel additive. It works incredibly well. If you are going to pull the head then just let the machine shop handle it. Some chemically clean valves, others high speed wire wheel it, others glass bead it.
Always let the machine shop do everything they can. Saving $100 by not doing something needed ie valve guides, seats etc, is always a false economy. You will wish you had spent the money a few months down the line. Local shops fully service my 5 cylinder turbo heads for about $300. The head comes back clean , skimmed with every valve and guide perfect. They run for years and really give the car new life.
While the head is out I do fit new “total seal” rings. That combo (fully serviced head and total seal rings ) really pleases 850 owners. The car is more crisp and responsive. I always throw in oxygen sensors as well as usually the worn head/rings has thrown a bunch of oil at them.
Thanks for the replies.
I have tried Seafoam a few times and it was OK. I have not tried Power Foam but from what I have read over at BITOG it works a bit differently – it’s a foaming agent that expands unlike SeaFoam which, despite the word Foam on it, is liquid and susceptible to hydro-lock whereas Power Foam is not liquid. These are the reasons why I was wondering if shooting Power Foam down the spark plug hole may have some benefits – it goes straight into the space between the valves and piston (at TDC) where it can expand and be in contact with the IN/EX valves and pistons. Pouring Seaform down the plug hole will just soak the pistons.