Limited disassembly of a 1980 IC 196

What a pain. Got the block stripped down except for the camshaft. The main and rod bearings were beginning to wipe, but nothing was scored or torn up. Let the machine shop evaluate the crankshaft's journals. Lots of sludge in the engine's sumps, but no cam bearing bits in the front sump. I suspect those are worn, too, but haven't come apart.

Mm's analysis was right - a tired engine. But at least nothing was disintegrating.

One of the first things I do is to weld a thick washer into the front sump and tap for a drain plug. That was one of IH's stupidest tricks to save a nickel. :icon_down:
 
Questions about the oil galley. All that is left to do to absolutely strip this thing down to bare are the following:

got all the little oil galley pipe plugs out except the last one on the outside of the block. That 1/8" pipe plug with the square end. Stubborn! Heat has been no help. Sawed a slot into it - impact driver is chipping it away. Cut off the remainder, drill a teeny hole in it and then step-drill it out?

2nd question: there's a large pipe plug in the rear of the oil galley (this one inside the bell housing end of the engine). Never seen a square drive that size - what on earth do you stick in there for a "wrench"?

On the front of the block is a welsh plug for the front end of the oil galley. Go ahead and pry it out?
 
For the side galley plug, you could have applied heat directly on the plug, and when its red hot, run a thin candle or crayon around the threads. The wax will wick up and in to lube the threads and unfreeze the situation (gramps old trick). Sounds like that boat has sailed though. Centering a tap-sized drill bit in the remnants would be my guess now. Then with luck you can pick out the old pieces like a slinky.

For the front welch plug, a self tapping screw and a claw hammer works every time.

And the rear plug you describe is bigger than a 1/2" socket drive? I don't remember ever having a problem here...
 
I did apply heat, it just hasn't broken the rust bond. It did work on one of the other plugs, though.

The plug in the rear of the block has a square hole about 0.325" across. Never saw that odd size before. Huh. 3/8" drive is what, 0.375? And definitely won't fit! Next size down in my experience is 1/4". Looks like I'll grab a cheap stubby 3/8" adaptor and grind it down to fit.
 
That just doesn't ring a bell to me. I would remember grinding a special tool to extract a square drive plug different from 3/8" or 1/2". I don't have a 4 cyl pic, but all of these are either 1/4" npt or 3/8" npt. I just can't remember having this problem.
 

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I do not recommend much heat. The risk of warping the block is high.

You are having the typical problem I have. I jigged and used a surface grinder to square up a 3/8 socket allen. Perfectly fitted to the odd plug. I still struggle and they still round out.

The plugs are soft and after a life of being threaded in I usually have end up step drilling 50 % them out and picking the remaining threads out. ..

the welch plug can be inverted by denting the middle in at the center or drive a punch through it . it will retract and come out easily..
 
I do not recommend much heat. The risk of warping the block is high.

I agree. I use an acetylene flame and keep the heat localized on the plug (or bolt, or whatever). I think the wax is what really does the trick.
But for sure, torch flame on anything carries some risk.
 
I used a small propane torch and kept it on the square protrusion, so I don't think I warped anything. That location on the block is quite thick, so should provide a bit of meat for tapping if drilling doesn't go perfectly.

Regarding that large plug in the back with the weird hole. I'll put a bit of heat on it to see what happens, but probably will have to resort to the drill.
 
Update:
got the weird oil galley plug out of the back of the block. 5/16" square. Ground a 1/2 to 3/8" socket adaptor to fit, and a little heat. It's out.
Got the funky rounded off 1/8" pipe plug out via step-drilling and heat. That long passage was filled with sludge resembling permatex #2.

Took everything to the machine shop Tuesday, just got the results this morning.

1) crankshaft miked out within standard specs and will (or he did) polish it. Need main and rod bearings.
2) pistons: block wasn't worn badly, and 0.020"s will work, May have to go 0.030" if availability is a problem with the silvolites. Jeff working on that.
3) piston rings: I've used moly in the past; Jeff suggests iron. Boost will be intermittent and probably limited to 5 lbs or so. Concern is durability? I'm open here...
4) deck. Machine shop said it was flat, so that's that.
5) cam bearings: Jeff sourcing those.
6) camshaft: will get to Jeff to send out for a regrind. Application has been stated here previously. Appreciate specifics.


The head is sitting on my workbench. Need to finish disassembly and grind out smog bumps before sending it down for work. I can detect that some exhaust valves feel loose in their guides. I see on this board that available exhaust guides May be problematic in getting best fit for valves? Best solution for that? Will have the head checked for cracks and flatness. I'm wary of old springs. Since I don't plan on running the engine over 4,000 rpm, and then rarely, could go with oem springs.
 
Mark pietz said:
Update:
3) piston rings: I've used moly in the past; Jeff suggests iron. Boost will be intermittent and probably limited to 5 lbs or so. Concern is durability?
Click to expand...
Not that Jeff is wrong but my personal opinion is that anytime I build an engine that will move toward more heat and loading I run a moly top ring. Even intermittent short term heat and high loading can increase top ring wear. You May be fine but what is the added cost really? Make sure you run proper end gaps on that top ring (.018 +). 5 pounds is going to make the dynamic compression ratio 11-1(8.25 x 1.33) so plan for that on this build

Mark pietz said:
6) camshaft: will get to Jeff to send out for a regrind. Application has been stated here previously. Appreciate specifics.
Click to expand...

Isky 190156 grind and lc applied to your cam .

Mark pietz said:
The head is sitting on my workbench. Need to finish disassembly and grind out smog bumps before sending it down for work. I can detect that some exhaust valves feel loose in their guides. I see on this board that available exhaust guides May be problematic in getting best fit for valves? Best solution for that?
Click to expand...

The exhaust guides take it in the azz on these due to the rocker geometry.
Silicon bronze guides only for this application .002-.0025 clearance. Don't use the so called pc type of seal.

Mark pietz said:
Will have the head checked for cracks and flatness. I'm wary of old springs. Since I don't plan on running the engine over 4,000 rpm, and then rarely, could go with oem springs.
Click to expand...

Don't use the original springs. I recommend the comp spring that is available from Jeff. Set it up @ 1.850. That will yield 80-85# seat. That is enough for your application. Forced induction is always trying to blow the intake valve open so you should run more than what you think. Valve area x manifold pressure peak is the increase in seat pressure you should run.
 
Wonderful progress.

Block is done. Bored 0.020" over, plateau-honed, and the silvolites fitted up
cam bearings set
got the camshaft ground to isky 156 specs. (0.050" ground off base circle so May need custom pushrods?)
timing gears were in excellent shape.
Crank polished and got the new main and rod bearings.
Flywheel surfaced (ground).
Rebuilt clutch kit from Jeff
crank, front pulley, rods, pistons, flywheel and pressure plate just back today from the balancer.

Will pick up all from moore's on Friday.
Curious to inspect the cam bearings and accuracy of oil hole alignments. Hopefully won't have to complete by drilling like I had to do once in the past.

Should begin begin assembling the "short block" in the next couple of weeks, then vacation. :icon_up:

bell housing, front cover, tappet cover, oil pan, intake manifold all tanked, cleaned, and painted. Drain plug bung welded into front sump of oil pan. Need to weld in 1/2" npt drain bung to tappet cover for turbo drain.

Headwork will have to wait until late August.
 
Got the block up on the engine stand. In the process of getting the block bored and plateau-honed, the issue of clearance wasn't really addressed. He did a great job and the clearance between the piston skirts and bores is 0.0035". Although that is the spec in the IH manual and the lower end for what hastings recommends for the svs, I hope that won't be too tight with some limited boost. I can always take it back to increase it (he won't be happy with that) if it would be a real issue.

The rotating assembly was balanced. A sheet came along with it with the weights of various parts. I'm not certain how to interpret some of the annotations. You can see where weight was ground off some of the rods and the crank throws.
 
.0035 is good for your application. Also where I set up my 152 t project.

Just watch oil temps like a hawk so piston temps are in control.
 
This engine should not have a cooling problem. It is set up with a 3-row radiator (essentially the hd cooling system for a 345 w/towing package), plus whatever internal advantages May come from it being an ic engine. But for peace of mind add a small oil cooler with a thermostat to permit flow to cooler when 190 degrees is reached?

I noticed that a stock 152 specs for 0.0025", so you added a thou. By nature do bigger bores need a bit more clearance?
 
Yea, add a large plate stack oil cooler and thermostat. Use 180 as a keep at temp. Must use a stat for the oil cooler as cold is as bad as hot.

My 152 was built with the intension's to turbo charge so I clearanced the bores and rings accordingly.
 
Robert,
some advice on this situation. I have the engine block turned over and the main caps removed. The machine shop lined up the holes in all the cam bearings perfectly. That's the great news. But the very odd thing is this. The holes in the webs that feed oil to the mains and cam bearings are slightly larger than 7/32". The oil holes in the cam bearings for 1, 2, 3 and 5 are likewise this diameter as I can pass a drill bit this size completely through. What caught my eye was the hole in the cam bearing for #4. It was visibly smaller, so I sized it. A 9/64" bit just passes through it. #4 also ultimately feeds the rocker shaft. Why would the hole in #4 be smaller than the rest? It's actually just as wide as that arc/groove on the inside of the bearing surface it intercepts. Should I drill this one out to match the rest?
 
Opinions vary but I leave the bearing hole diameters alone so long as they are not overlapping and partially blocked.. Never had a problem with rocker assembly oiling.
On another note, only 2, 4 and 5 do more than oil the cam bearing 2 and 4 also supply oil to the valve train as you know. Drilling it to match #2 is your call. Suppose it can't hurt to match the two. Just make sure you deburr the drilling trash and don't let the drill jab the other side of the bearing. :icon_xp:
 
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