The Stovebolt Site Forums The Shop Area Engine Shop Antifreeze Leak

While adding antifreeze to my newly rebuilt 216 engine for the first time, antifreeze started coming out of hole on the left side just below the manifold. Can anybody tell me what the hole is used for and what should I used to plug the hole that has threads in it.

Thanks

Charlie

I believe it's 1/4" pipe thread plug.Some blocks have a radiator petcock screwed in that hole.

Yes it is a drain. I have a petcock in mine.

Thanks Boys

Gentlemen,

Ive tried to use two differant sizes of pitcocks, 1/4 and 1/8 but they were too big, I've tried 1/4 bolt too small 5/16 18 thread its starts in the hole then stops with only a few threads in. Can't find a 5/16 24 thread count, any ideas on what to use next!!

Try and get a old rad drain valve my block was leaking from the valve and I just got a rad drain from the local rad shop

Can you post a picture of the hole your trying to plug ? In a way it sounds like you might be describing the bell crank threaded hole.

if it is the plug and the lower rear part of the drivers side of the engine close to the hole in the bel housing that plug is for draining and flushing the block. i have two different sizes on my trucks 1/8" and 1/4" npt. there also is a smaller pipe tread than 1/8" and have rarely seen them.

Here's a pic of the manifold side of my 216 - http://i360.photobucket.com/albums/oo45/dalbuie/41%20Chevy/216.jpg - my petcock is on the right of the engine (looking at the pic).

If you can point out where yours is leaking form on this pic it should help.

Cheers

Its the hole inbetween the freeze plugs Im new at the photobucket stuff I hope this works. http://i835.photobucket.com/albums/zz276/hdstickel/1953%20Chevy%20Engine/IMG00046.jpg

Are you sure that's a 216 ? My 1951 216 has only one hole and the bell crank stud is screwed into it.

My 1954 261 has the two holes as yours does.The bell crank stud is screwed into the boss closest to the rear of block.I had to screw a plug in the other hole,I don't remember what size of bolt.

Oh yea its a 216 with babbit oil system. Still haven't been able to find a bolt that will fit. Tried everything from 1/4" to small and 5/16" 18 thread count starts in the hole but only a few threads then stops. Can't find any 5/16" with more or less thread count.

5/16 24 fine thread sounds like it would fit. Going to need some way of sealing though, gasket, o-ring, sealing washer, silicone, etc. due to the fact that straight cut thread don't seal well.

i just got my 59- 235 back from being rebuilt on thursday. after looking at your pic and looking at my block, the hole(front one) is for the stud that holds your throttle linkage. mine is 5/16'-18. that stud screws into the water jacket of the block. i took mine out with some effort and cleaned up the threads and it was tight going back in. i chased both the stud and the hole with my tap set and it screws in all the way with ease. with all the years of crud build up the treads just need to be cleaned up.

The hole mentioned is used for the throttle linkage on my 216 - but my 216 doesn't look the same as yours.

The 216 I have only has the one whole the same as bowtietim. I think the early 235s were also low pressure babbit engines, what's the block number on yours?

Ok got the leak fixed with a bolt but as I continued to fill the engine with antifreeze another leak started on top of the engine near the valve cover a bolt hole towards the rear of the engine any ideas what is suppose to fit here?

It's probably the hole for your temperature gauge sender .