MTFCA Forum

I have a 26-27 block that has a chip (not more than a quarter inch deep (as measured from the top of the guide) and not more than one third of the circumference of the top of the guide. Do I need to repair this, or will it affect anything if I just leave it 'as is'? I don't have a picture; next time that I go to my parts, I'll take one.

Me, I would catch it next rebuild and not worry.

big2bird wrote: ↑

Thu Oct 29, 2020 2:50 pm

Me, I would catch it next rebuild and not worry.

That's just the point. The block is not in use, and is a spare "rebuilder". Are valve guides replaceable? Is it a problem serious enough to address? I can't see where it would affect the alignment or support of the lifter in the guide. If anything, I would think that it might add additional lubrication to the lifter.

Terry, l would not worry about it on a slow running T engine.
I’ve seen so many small engines that broke a timing belt, bent the valves and broke a quarter of the valve guide off.
The machine shop just put new valves in and the head was put back on the engine.
I bought a Daewoo that broke a belt and bent a bunch of valves and broke most of the guides. I figured if the dealer could get away with doing that, I could too.
I put new valves in and it ran at least two years that I know of.
One the T engine a machinist could drill out the block and install a guide.
Ok, I just went out and looked at a late block. The guides are so long that with a quarter inch missing they’re still longer than needed.
Don’t worry about it.

Years ago people use to cut off the guides so they could adjust the three wrench lifters, so if they where not worried about it then why now?

Are you referring to the valve guide or the lifter boss ?

When I had access to a mill, I use to cut about 1/8” off the lifter boss so I could more easily adjust the lifters. It didn’t seem to do any harm.
If Terry really is writing about the valve guide, I can’t see 1/4” missing causing too much harm. I suppose it could be welded and ream out but knowing my luck it would result in four more cracks.

RajoRacer wrote: ↑

Thu Oct 29, 2020 6:58 pm

Are you referring to the valve guide or the lifter boss ?

Thanks to everyone that has given their ideas and opinions. Unfortunately, I had a 72 year old senior moment when posting originally and Steve caused me to catch it. I don't have a chipped valve guide; I have a chipped lifter boss, but some of you have answered my question because you mentioned a lifter boss. I'll not worry about the chipped boss. In fact, I may just take my angle grinder to all the lifter bosses and take off an equal amount off of each one. Thanks to all.