79 scout project

rbreen3

New member
So I have a 79 Scout that im trying to finish. It currently has a 345 in it. And I need some advice as to what I should do w it. I want to either rebuild the current motor or drop a 350 in it. What would be the cheaper of the 2? And how difficult would it be to swap it w a 350
 
Welcome. I moved your thread to a more appropriate section. Have you done a thorough assessment of the 345 condition? They're pretty durable engines and have been known to faithfully log significant miles. What other areas need attention on this rig? Usually the list is quite extensive. How do you plan to primarily use it? Would a good tuneup buy you some time to focus on other areas of concern?

The IH sv8 engines are quite costly to rebuild in a thorough and proper manner. It is difficult and costly to realize dramatic performance gains above stock from these engines. They breathe poorly and the rotating mass is quite heavy. It takes a fat wallet to get a 345 appreciably above 200 hp at the rear wheels.

Do you have a fresh, 4 bolt main 350 long block ready to drop in? Everybody and there aunt martha has swapped a sbc into their Scout. You can find build threads everywhere for guidance on that process. What about a transmission? Whatever you have now isn't going to simply bolt up to some other block without being adapted or replaced. If you swap the trans also, then you have married transfer case mating issues to overcome. None of these hurdles are insurmountable. They've been dealt with numerous times in a variety of ways by Scout owners going back more than 20 years. The information is out there.
 
+1 on ihpaststrever's comment I'm rebuilding an IH 345 right now. All that weight and flat torque curve really work well when off-roading and trailering. Tell us what's up with the 345.
 
I don't really have any other issues w it. The motor has 78000 original miles and leaks oil out of about every hole tho. I want it as a daly driver. Im leaning towards replacing seals and gaskets for now to keep costs down and go from there.
 
These blocks are tough as nails and come factory with a lot of stuff you'd pay extra for on a 350. For starters you have a steel crank there with induction hardened journals. The cast iron in the block is so hard that after 300k miles the hone marks could still be seen in the block I'm rebuilding.

I'd check the compression on the cylinders and if that and you've got oil pressure at idle, then the leaks are fairly easy to fix. Is your pcv valve and flame arrestor on the drivers valve cover in good condition?
 
Unrelated question I have a 345 (strong as a box) I have new boat style rockers are these interchangeable with the welded ones??
 
unrelated question I have a 345 (strong as a box) I have new boat style rockers are these interchangeable with the welded ones??

Yes, but......you have to rotate the rocker shaft 180 degrees to use those. The oiling system of the rocker shaft demands it!

With welded rockers - the shaft oil holes face up.

With boat style rockers - the shaft oil holes face down.

If you also have new or rebuilt rocker shafts to go with your new boat style rockers, then use those with the oil holes facing down and don't reuse the old shafts.

Different push-rods are utilized with the two types of rocker arms. "ball-ball" are used with boat style rockers. Ie. A ball on each end.

Make sure the feed oil holes in the head (one per side) have the oil feed rocker stand mounted on that position and that the oil passages are clean and free flowing in all parts.
 
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