The Ultimate IH Fourbanger

[Michael Mayben]

Ain't this a purdee site??? A collage of oil/sludge, cam bearing chinks and chunks, coolant, carbon, a bolt from hell, and quite a bit of unidentifiable shit! Keep in mind, this motor was runnin' when jerked...look at the first pic in this thread and you'll see it.

 

[Michael Mayben]

Now we're gittin' sumwheres...the oil pump intake screen is sludged as bad as any engine ive ever seen! How'd this motor lubricate??? Only by splash like a 50 year old briggs and stratton!

You think pourin' atf through the carb will clean this one up? Think replacin' the lifters will make the sludge disappear? Will moto-nu rebuild this motor for me, ya know, that piston rings and bearings inna can shit??

 

[Michael Mayben]

So this can be a learning experience for summa you engine-noobs, here is what we refer to in engineslangdom as a "spun bearing".

Look at crank rod journal #4 (on the right side of the pic.

When I pulled the cap off, I found the bearing shells "spun". That means that they seized to the crank journal at some point (lack of lubrication), and started turning with the journal instead of being held stationary by their "keys" and critical fit. So the bearing was "spinning" inside the rod big end. That in turn destroys the crankshaft journal.

The same thing can happen with the main bearing inserts, and most especially with the full circle cam bearings.

Whatcha see there is a pair of bearing shells that are about half the thickness they should be, only the backing remains, the actual bearing material disappeared long ago.

 

[Michael Mayben]

And here is the spun bearing (top) compared with a wornout (but not spun) bearing set from rod #3. Notice how the shell is all crushed and distorted. This motor was knockin' like a diesel.

All journals on this crank are badly scored. It's no use to measure it. This one will become a core now and sent to our crankshaft rebuilder. They will completely inspect and weld up as needed. The rear seal surface on this one is also fooked, so they will install a repair sleeve.

Once it's cleaned, welded as needed, and magnafluxed, it will be have the journals ground "undersize" and then cleaned again and packaged with the correct size rod and main bearings and put on the shelf for resale. I'll be using a 196 crank in this block, so the unit I have will also be sent to the supplier for a grind/micro polish.

Once the entire rotating/reciprocating assembly parts are gathered, the complete set of parts will be balanced.

 

[Robert Kenney]

here's the crank hub I'm gonna use, it's ready to ship down to Robert so he can machine the magnetic trigger wheel for the ignition system and mate it to the hub.

This one has a damaged section where the oil seal rides, so it will get a repair sleeve installed. Once I get the finished unit back from Robert, I'll mount the pulley and it will go with the crank and the rest of the rotating/reciprocating parts (including the fresh flywheel and clutch assembly) to the engine balance dude up in portland for completion.

Send that red thing down and I will do what needs dooing then send it back to ya. I will also send you the other stuff you need for sonja's deal.

 

[Michael Mayben]

send that red thing down and I will do what needs dooing then send it back to ya. I will also send you the other stuff you need for sonja's deal.

If them ss checks would show up like they supposed to I'll be orderin' up the mag trigger guapo and get it all in the mail to ya! In fact...I'm thinking about making a "trial install" of the mag trigger system on the runner 196 in the scoutractor now so I can get the bugs worked out!

The head I'd set aside for this build has been disassembled and is really nice! So it will be cut and gouged by dave soon and then sent out for finishing. Dave now has access to a friend's valve grinding/cutting equipment but it's still all boxed up. If we can get everything unpacked and set up, then we'll do the seat/valve cut ourselves.

I assembled a nearly virgin nine stand rocker assembly for the motor last night. I still need to rob a few more parts off another donor 152 today...I'm onna roll.

Since I have mikeesquare's crappy 196 crank on the floor now, I'm gonna drop it into the 152 block today also and check clearances for the counterweights and such. That 196 crank is much larger in the counterweight area than the 152!! More pics to come.

Dave found a 196 crank at his core supplier buddies' place a few weeks back and snaked it. It is also in bad shape. So it has gone to the crank grinder for a freshening and will be put in the ihon inventory (as a kit with bearings)...first come...first serve!

 

[Michael Mayben]

This shot compares the 196 crank on the left, with the 152 crank on the right.

The 196 has significantly greater counterweight mass. Haven't put each on the scale yet, but I'm guesstimating the 196 is about 20lbs. Heavier than the 152.

 

[Michael Mayben]

Here's a shot of the 196 crank installed in the 152 block. No issues regarding any clearances of the counterweights and the block!

Closest point of crank-to-block is 1/4".

Depending upon which rods and pistons I end up using, the replacement pistons May have to have some machine work done on the skirts for counterweight clearance...but we won't know until we have the parts on hand to test.

So Robert...I guess it's time to home in on the rod/piston combo on my end so I can finalize the plan!

 

[Michael Mayben]

Here's a shot of the counterweight-to cylinder bore clearance, the angle here does not really show how much clearance is actually there.

 

[Michael Mayben]

This shows the tightest clearance point...where the oil pump outlet bolts to the block...that is 1/4"+!

 

[Michael Dimock]

Hmmm, I thought that crank looked familiar!... good to see that it is being put to good use! Damn that engine is going to be clean. By the time I'm ready to go with the 196, you'll have all the quirks worked out and it'll be a breeze in the engine rebuilding.

 

[Michael Mayben]

I'm thinkin' we put the 152 crank in yore motor, by gittin' the compression down way low, we kin run it on coal oil or drip gas???? Or turpentine ya kin make yoreself.

Layin' the 196 crank over in that rotten 152 block beside it didn't make it look any better though! Both cranks are equally focked!!

 

[Robert Kenney]

Mm,
I am posting details of my fiat stroker build because it is some what relevant and well documented.
Started life as a 1800 cc 87hp mill. I stroked it up 11mm(.433")
and bored it 1mm (.03937") to net 2050cc and 160+ hp. I designed rods and pistons and had them made here in (hotrod heaven) socal.

The block picture I posted shown the typical clearancing needed for the larger stroke. The rods were speced with a low profile big end so machining would be held to a minimum and the stock oil pan would still work.

Remember the IH has a lot more surplus room to accomodate the stroke increase so I expect only the bottom of the cylinder bores will need to be modified to clear the rod I beam.

 

[Michael Mayben]

Thanks for the profile of the fiat Robert! That should really help other folks that May have an interest in what we're doing!

I'd forgotten all about the "notching" deal at the bottom of the cylinders!!!! I was more concerned with having to mod the piston skirts. But I just don't see any way to finalize all the clearance stuff until I have the rods and pistons we're gonna use in hand.

But no matter what, as you say...there appears to be plenty of clearance space in the bottom end of these tractor motors.

Just for my own curiosity...does that fiat mill have a "balancer" shaft or is that a quill shaft for an accessory drive I see???? And this is inna spider or a x1-9???

 

[Robert Kenney]

Just for my own curiosity...does that fiat mill have a "balancer" shaft or is that a quill shaft for an accessory drive I see???? And this is inna spider or a x1-9???

The shaft pictured is a carry over from when the fiat twin cam had a block mounted dizzy. It also had the mechanical fuel pump eccentric on the end that I had to machine off for rod clearance. The old dizzy location still drives the oil pump so the shaft needed to remain.

The engine is in a 124 spyder.

To further this a bit, I recommend that all of the clearancing needs to be done before any final block machining or boring is completed. First pick your crank and rods and have the crank modified to need and rod fit then machine a piston for a preliminary mock-up and clearance block needed. Then measure the finished deck and compression height requirements and choose a piston or have them made. I usually leave the piston in the hole .010 or .010 below the expected finished location to allow block desk surface refinishing.

 

[Michael Mayben]

While waiting for paint ta dry on some distributors, I thought I'd play with my own stuff a bit.

Needed to clean up a lifter chamber cover and get it ready. So I robbed one that was a later model cover set up for a pcv connection off another engine that has seen some time underwater. Typical ratty po piece of crap!

The cover came off too easy! Normally takes a bunch of effort to unstick 'em. Ya can see in this shot that in the past, someone cut the connecting hose, even though all the pcv and manifold adapter for it were still in place, just had the hardened rubber hose sliced off.

 

[Michael Mayben]

The round fitting that is bolted to the cover connects to the pcv valve scruud into the intake manifold adapter.

Now ya can see why someone cut the hose...the sumbitch couldn't breathe!!!!

In all my years of scruuin' with motors, I've never seen one that has such a large breather passage that is totally sludged/clogged with no opening to the pcv! If ya just pulled periodic maintenance on this pcv, that would not have done nuthin' as far as allowin' the motor to breathe!!!

So this will be one more priceless part saved from the crusher.

 

[Michael Mayben]

Now here's the backside of the cover showing the baffle for the breather connection. Notice the lack of sludging on the sheetmetal...someone has scrapped gunk off in the past, ya can easily see that.

So someone went to the trouble of pulling the cover, and cleaning the backside, but never cleaned out the breather tube!!!! And then no doubt pissed and moaned about "all IH crap leaks oil!". Well hail yeah...I guess so, if you were this constipated I'd say ya would have sum trouble gettin" yore motor revved up too!

 

[Jaxx008]

Ok so you drug me into your stroker 4, and now I am curious about the progress/success. Any new status on this build? Did you resolve your piston/connecting rod combination?

 

[Robert Kenney]

ok so you drug me into your stroker 4, and now I am curious about the progress/success. Any new status on this build? Did you resolve your piston/connecting rod combination?

Unfortunately both michael and I have been very busy with other stuff. The rod deal is a fairly easy situation to figure out.

Pistons will require a custom design based on the stroke you choose.

For a 152/304

you can use a bbc 6.135 c to c rod and have the stock crankshaft rod journals welded offset ground and narrowed to fit them and that is the cheapest solution.

Next best is a custom forged steel rod to fit the oem bearing and weld and offset grind the crank to what ever your heart desires within the physical constraints of the block.

Other than this we will have to wait till such free time pops up.