OK, I bought a toy and it arrived a week and a half ago. 1989 Formula 350. I bought it on ebay and after having so many good experiences with buying stuff on ebay I learned a lesson. So besides the other things that are wrong with it that I can take care of (interior, spot rust, no radio) I took it in to have my mechanic look it over for exhaust leaks/shocks/struts and he shows me where the engine block has a leak. I had notice a small puddle of coolant but didn't think much about it.
OK, so down the road I knew I would have to rebuild the engine but not 1.5 weeks down the road. My question is.... Since the engine still seems to have plenty of power and it already screwed is there a product I should put in to try and seal the small crack? I definitely am not going to rebuild it right now. My mechanic suggested using one of the radiator stop leaks. As I said the engine still puts out a bunch of power but it will leak every once in a while. Should I not tighten the radiator cap to keep pressure from building?
Thanks

 

You need to be able to see the crack and the damage that is done. You can do a couple of options, but we need to know the extent by a visual reference.

 

If it does not leak bad I would just check and fill the coolant as necessary .

 

The area where it is leaking is on the passenger side 3/4s toward the front of the engine. It barely leaks and sometimes doesn't leak at all over night. I drove it for about 3 hours Sunday afternoon/evening and it didn't leak at all Sunday night. I think I am going to try a stop leak along with keeping the cap loose. Lower pressure= less chance of it leaking. I agree with the adding coolant option also. I will be block hunting soon. Hell, I may end up just getting a crate engine and popping it in. I have enough invested already it needs to rock and roll. lol
Mechanic at first thought it was a blown head seal but when we got a better look it was obvious the coolant was coming from about an inch below where the head sets.

 

i read a package of JB Weld and they were takling about using it to seal up a cracked engine block and saving thousands of dolars, don't know how that works with the heat and what not but someone might b able to pop in here and say whether or not it's a good idea, but i agree with kuulkatdadieo with checking the rest of the engine to see the extent of the damage, but then again at that point of pulling it and tearing apart it's not worth putting the old block back in, lol.

 

That is how I feel. Why go into it if it will just need to be rebuilt or replaced anyway. I am just looking for a cheap easy part time fix. Keeping an eye on coolant and refilling with 50/50 coolant water is the #1 option right now. A year or two down the road a rebuild/replace will be the way to go.

 

well unless someone says otherwise i would suggest jb-weld, it may cure your leak until a year or 2 down the road when your ready for a swap, it says it right on the package so i don't see why it woudln't be ok for it, you just may need to do a couple coats fillings depending on how big/long the crack is.

i think i heard of something called liquid weld or sumthing like that, i think it's similar but not sure.

 

Where in TN are you located? I need to find some other 3rd gen owners in the Memphis area to pool our resources for parts. I hadn't thought about how many parts have now been disontinued.

 

I'm in Middle TN. About 50 minutes up I-65 and to the North of Nashville.

 

Are you sure that your block is really cracked? I have seen cracked heads, and heard of blocks cracking from freezing up with water - but those never ran again. If it is still running fine I would be more inclined to look at the soft plugs, or a bad head gasket.

 

There's a good possibility that it's not a crack at all, but rather, a freeze plug that has rusted through from the inside.

Try the stop-leak stuff first. That'll keep the car on the road, maybe.

THen when you get the chance to do some investigation, use the ultraviolet dye you put in the coolant. Makes it VERY easy to find.

If it IS a freeze plug, then it's a good news/bad news kind of deal. Good, because your block itself is OK. Bad, because there's a total of 8 of them (2 on each side, 2 on the front, 2 on the back), and if ONE has rotted through, the other 7 can't be far behind.

 

We could see the exact spot where it is leaking. I looked for anything near it that could be the reason and nothing is near it. I'll try to get it to leak in an hour or so after I pic it up and I will take some pics if I can maneuver the camera in there.

 

Alumaseal Radiator Stop Leak. The stuff in a small plastic cylinder about 1" diameter. Its a powder. On a small leak its almost 100% sure fix. Missouri Mule is good too but you probably won't find that local.

 

If you want an easy posible fix I would try Moroso ceramic block sealer it is better than any stop leak.

For a more permanent fix:
http://www.belzona.com/enc.aspx

This is some really cool stuff. I had the salesman in my shop a couple years ago and he showed me a video of some repairs that were done with this.

 

Yep, the Belzona is good stuff. I've used it to rebuild the counterbores that were worn out in old Cummins blocks. After you build it up, you machine it back to factory spec and install the new liners.

That stuff is amazing...

 

I used JBweld to fix a 2" long crack in the lifter valley of a 318 block and it never leaked. Get it good and clean first.

A word of warning about Moroso ceramic engine seal- it's really serious stuff. I wouldn't use it unless everything else didn't work. If you do make sure to bypass the heater core during the process- it will probably plug it up.

 

Just thought I'd give an update of what I did. After searching the internet I found an article about K&W engine block seal. It said to not follow the instructions on the bottle but to clean out all the antifreeze then pour the stuff in and fill with water then run it and drive it. Drive it for at least a few hundred miles. Then clean it back out and refill with antifreeze/water.
I did as instructed on that page and noticed the leak stopped almost instantly. I drove it for at least 300 miles before flushing it out and doing the antifreeze water. Well that was 2 weeks ago and it has not leaked one bit since. Just thought I'd share since there may be others out there in the same boat as me. Weekend fun driver and I was not financially ready to replace the engine., It still runs great and no leaking coolant.