F-head cracked block.... thoughts ?

What I thought to be a blown head gasket turns out to be a cracked block. I have a crack dead center of the engine where the middle head bolt threads in and a crack between #4 cylinder and exhaust valve. I can see where the cracks were drilled out and welded at one point in time . Can a good machine shop save this block? If not , I will be needing another motor if anyone has one hanging around.

I appreciate any input anyone can give me

Thanks

P.S. How do you post pics here?

 

I'd be looking for a different engine.

 

4.3 liter chevy or 225 oddfire. never look back.

 

I understand a crack in this location is a common end for these engines.

+1.

Lots of 4.3Ls in the yards, or in a donor vehicle. There are some modern 4-cylinders that are popular swaps too.

The site will not host your pictures. Use a picture hosting site like Photobucket and put links or hot-links in your message.

Here's a thread with instructions for using Imageshack as a host. http://www.fsjnetwork.com/forum/viewtopic.php?f=31&t=1152

 

I have been toying with a 4.3 non-balanced swap. looks like now is the time, unless I can find a replacement f-head relatively cheap.

Thanks !

 

L and F 134 exhaust cracks frequently are had between the #2 and #3 exhaust valves.
The cracks are generally manifest from letting the exhaust valves get into bad condition.
The block can usually be stitched in order to seal the crack

 

Beware of a simple engine swap... Its a slippery slope. My F head cracked a piston... Well, I wanted a 4speed too... Led to a full rebuild with everything being changed out but the frame and body...

 

I bet its been terrible.....

 

I had a similar (F-head) crack repaired, sucessfully. But hard to say how bad yours is, since it's been repaired once already.

 

Exactly what I am afraid of. if I can fin another f-head, I will be driving it in a week. If I go for a swap it will be a year.

 

Don't forget the ford lima 2.3 might be a hair simpler.

 

Lol... I started mine in early 2013... Hopefully this year it'll move again... It was only supposed to take a couple months or so...

 

I have an extra Fhead sitting in my garage. I kept it as backup but I am going to go with a 4.3 sometime this year. You are not real close but if you want to PM and talk about it feel free

 

I have a dead f-head as well. The crank has 1 bad rod; crank may be beyond grinding; valve margins are gone; significant ridges in the cylinders means at least a complete rebuild. The poor old girl has just been plain worn out.

The 4.3L I measured was a little shorter than the Hurricane and weight is ~50 pounds heavier. I have been toying with the idea of a 4cylinder s10 2.2l or 2.5l. The 2.2L from my research is ~100#s lighter than the hurricane with comparable torque and ~40+ hp. The stock clutch; brakes and cooling systems should be adequate assuming they are adequate to start. Hopefully the transfer case and trans could be left in the stock location to keep the driveshafts the same.

My stumbling points are the cost and time. Novak has adapters in my case will easily eclipse $500 + the S10 for parts. I estimate in the range of ~12-1500 by the time I would be done...

I hope this helps some.

Rich

 

You might consider one of the Colorado 5 cylinders.

 

I found a Mercruiser 4 cylinder while I was searching for ideas. 183 cu in with the Chevy bell housing.

 

That and the Chevy II 153 swap have been done a lot. The 181/3.0L marine/industrial engine is a 153 with a larger bore. I think the main problem for most swappers is the scarcity of those engines. You can, however, buy these engines new from GM - http://www.gmpowertrain.com/2013_pdf/FHR_REV_3.0L_Indust_122112.pdf.

Apparently the Ecotec engines are also popular swap material, but seem not to have found their way into Jeeps yet. http://www.s10forum.com/forum/f105/the-ecotec-swap-how-to-56k-warning-494496/ With oddballs like these and the Atlas engines (Colorado etc) you need to think about driveshaft and front axle clearance. Most of the popular pushrod engines have a rear pan sump, and you still have to be aware of the drive shaft clearance, usually at the starter.

 

When I rebuilt my F head 19 years ago it had all the journals bad and spun bearings. I had the crank welded. its where they deposit metal in either spray form or a submerged arc then cut and polish. good as new. one thing to remember is to make sure you keep the shims not eh front of the crank. they set your thrust bearing clearance. I was dumb and left mine on when i sent it off to the crank grinder. I also left on the tapered dowel pins. this was before internet so they were just about unobtainable. It wasn't too bad then to have it repaired money wise, it might be now.

There are rebuildable F heads out there. unless you're going for restoration, go with a newer better engine. more parts availability more power, less weight and more support. Either way its money

 

I have found someone here local with on that he claims has been rebuilt and he has receipts. I am going to try that route. if it falls through, I will pm you

 

Slippery slope or not, the only way I would spend money rebuilding an F head would be for a complete restoration project. As far as swap candidates go, I think the 4.3 is the only logical choice if you want to keep the rest of the drivetrain. Very easy to source, wide availability of relatively cheap quality parts and they are available everywhere. Not to mention the possibility of factory EFI. As for engine weights, the 4.3 is actually 45 to 50 lbs lighter than the F head. You won't be sorry doing this if you actually want to drive the Jeep.