ycanby

Farmall 656 gas Exhaust manifold replacement

Recommended Posts

Hello, I has wondering if anyone had experience with the new replacement exhaust manifolds for the C-263 engine. Is there any problem getting them to match up and bolt up with the existing US made factory intake manifold? Also what is the best way to get the four long bolts out that hold the two together. Looks as if they have been on there for 52 years. I can't see it being very easy.

Thanks in advance!

YC

Share this post


Link to post
Share on other sites

I do not know of a replacement manifold that fits the hood of a 656 very good the 656 is the only tractor I know of to used that manifold. As far as getting the bolts out good luck you will need it sometimes I have had all four break off and had to drill out the stubs sometimes I have been able to just weld a nut on the stub and turn it out maybe once or twice in my life have I had all 4 bolts thread out and I have changed a lot of manifolds.

Share this post


Link to post
Share on other sites

We will usually cut the heads off the bolts and separate the manifolds  that leaves 

a lot of bolt to work with and you can see if the bolt is turning or twisting.

Share this post


Link to post
Share on other sites

The 4 and 560 used the small pipe exhaust manifold.  I did install one on a 656 several years ago and , although it was the small pipe, the two pieces fit together like  a saddle on a sow.   Also put one on another 656 few years later and went with complete, intake and exhaust manifold.  First one came in box with broken counter weight.  Next one the heat riser was assembled wrong. Had to do some reworking on that.  

At any rate, you will probably have to    have the manifolds resurfaced when bolted together for alignment purposes unless you are really lucky.  Also, made sure you get the heat riser in intake cleaned out good and all parts in good proper condition.  I have found sand blasting that carbon out of the exhaust part in intake manifold works really good.   Also, there are two different style manifold gaskets so have to keep that in mind.  Best one is steel only on exhaust and steel with embossed material on intake which requires manifold to be allowed to align (four bolts able to allow manifold to creep) when bolting onto head.  Most aftermarket gaskets are same material all the way across and easier to install but give more problems. 

Share this post


Link to post
Share on other sites

I did the job you mention on my Farmall 656 about 10 years ago. I just looked up again a few minutes ago and if you want a correct fitting manifold that doesn't look like something Rube Goldberg made, you will have to bite the bullet the same as I did. There is only one supplier of the correct manifold, and that is CIH, and as normal they are very proud of their parts. The part number is 390988R2 (item 13 on page B65 of the C263 parts book). I remember it being about $600 US funds. To get the bolts out we cut off the heads and separated the manifold. Then with a oxy acetylene torch we heated up the bolt thread area from the side of the intake manifold. The bolts all screwed out easily afterwards. When cool we chased the threads on the intake manifold before installing the new bolts and gasket. I also repaired the heat riser valve at the same time. As far as assembly went we tightened up the 4 bolts loosely and then attached the entire manifold to the cylinder head. We then tightened up the cyl head exhaust manifold bolts and the 4 bolts on top holding the two manifolds together simultaneously and I had no leaks. It still works fine after about 500 hours in the last 10 years. But like I say doing the job properly isn't cheap. But it was a case of doing it right the first time and with good results afterward.   

Share this post


Link to post
Share on other sites

I replaced our 656 Farmall's manifold this fall with the intake and exhaust assembly from Steiner.  All I had to do was plane the gasket surface (had a machinist check it out and it was almost perfect with only one low point) and install a pipe reducer to use the original exhaust pipe.  No other modification necessary. Decided to stay original size because everything internal and carburetion was standard; also didn't feel like cutting the hood.  The governor linkage did not even need to be adjusted. One thing that was mickey mouse was the counterweight--set screw too loose and too soft to tighten well. ended up buying a new set screw with allen head instead of their torx.  first time I'd ever stripped a torx screw head instead of the driver!

International model might be different. I think I saw a different part number on the CaseIH parts list.  Steiner lists a bolt on adapter that offsets the outlet towards the valve cover for 4/560, it may work for other models too.

That reminds me of the other let down, the holes pre drilled and tapped for the adapter were drilled through so a couple bolts had to be bottomed out to seal the leak.

So far so good, but we'll find out during haying season '18

 

-karl f

Share this post


Link to post
Share on other sites

I agree with George 2 on his methods.

The Gas Axe is your savior.

That is the way we done it in the shop.

The only thing better is to get the torque wrench out.

When the heat riser works right, those tractors are fun to drive.

Share this post


Link to post
Share on other sites

Used the Stiener complete manifold with 706 pipe and muffler on my 656 didn't  have to modify  anything   it runs great. Mine has the bar style  grille  like the 756.

Share this post


Link to post
Share on other sites

Did one on an industrial and at that time the manifold was made from unobtainium so I had to fill and relocate the hole in the hood.

Definitely cut the heads off and use the hot wrench on the stubs. Get a heat riser kit if it needs one. I've had no problem with leakage at the joint.

Share this post


Link to post
Share on other sites

I had pulled the manifold off to replace the gasket, which had blown out on the forward exhaust port. Ordered new extra thick washers on ebay and when they arrived I put it back together with new bolts. Did the least I could do before firing it up and testing it for leaks. It was leaking in the exact same spot where it had blown out before. Took it back apart and gently cleaned up the exhaust part of the manifold where it contacts the head. I could tell the exhaust ports were all slowly deteriorating, but the intake ports were like new. After chipping off rust flakes with a chipping hammer , and a gentle brush with the grinder I put it back on the tractor. Tightened her down evenly and fired the tractor. No leaks, was totally surprised. I let it get hot, then tightened the bolts again, and finished putting it back together. Went ahead and ground two loads of feed with it, then retightened the bolts a bit more. all seems well though I suspect only for awhile. I noticed that the exhaust manifold metal where it seals to the head is definitely thinner than the intake metal. Sooner or later will have to replace the exhaust manifold. That leads to a couple questions. In order to part the one from the other it does seem best to cut the heads of the four bolts holding them together. At this stage will the two separate easily leaving the four headless studs sticking out of the intake, or will they still need persuasion to come apart? Also what is the heat riser that is mentioned often here. I take it it may be a flapper that cases heat from the exhaust manifold to warm the intake when the engine is cold. Seems when I bought mine in 1985 it did have a bimetal coil on the outside of the manifold , but it soon fell off and the rod that it turned has long been seized. Is that thing worth reactivating? I know the tractor is cold natured when first started, but once it warms up it runs fine.

Thank you all for the help!!, YC

Share this post


Link to post
Share on other sites

After you cut the heads off the bolts holding the intake and exhaust manifolds together you will need a torch (hot wrench) to warm up the sire of the intake manifold beside the headless bolts. They should come out easily using Vice Grips to clamp the bolt. They run nicer with a functioning heat riser valve.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now