Re: [ihc] 266 w/ knock -- forensics help requested!

["Allan Ericson" <lowvolt@xxxxxxxxxxxx>]

----- Original Message ----- 
From: "Steven Stegmann" <steve.stegmann@domain.elided>
To: "Eighteen Rabbit" <thor7358@domain.elided>; <ihc-digest@domain.elided>
Sent: Friday, May 21, 2004 6:30 AM
Subject: Re: [ihc] 266 w/ knock -- forensics help requested!


> Kyle,
>
> That strip of soft metal is a bearing insert.
> Guaranteed!  3/4 inch wide sounds like a cam bearing.
> Crank bearings are wider.
>
> When I rebuilt my engine a couple years ago, due to a
> knock in the engine, I found the cam bearings eroded.
> They were still in place but the exposed surface was
> worn away.  Never did find any identifiable metal in
> the engine.  My knock was worn cam lobes which
> prevented the lifters from smoothly following the cam
> contours.
>
> You need to tear that thing down and replace the cam
> bearings and probably the cam too.  Have a machinist
> check the cam bores to see if they are too damaged to
> take new bearing inserts.  May need to align bore the
> cam. Replace the cam and lifters as a set.  If the
> ones you inserted show no wear then you can probably
> use them.
>
> The cam comes out the front of the engine but the rear
> cam bearing comes out the back of the engine through a
> hole closed by a simple plate behind the flywheel.
>
> You also need to check the oil pump for metal damage.
> Most likely the filter stopped the metal from going
> anywhere else.
>
> When you tear this thing down do **not** reuse the
> connecting rod bolts.  They are tightened to yield
> when installed and should not be reused.  They ain't
> cheap, but if they fail...
>

I'm with Steve on this one. Low oil pressure in these engines is usually cam
bearing failure.

The original problem sounds like piston slap. Also a common problem in 40
year old IH engines.

A 304 bolts in where there was once a 266. Outer dimensions are the same. A
345 or 392 will also replace a 266. 3/4" wider and somewhat taller. A used
engine of this family can tide you over if you want to rebuild the 266. I
just used a 304 in my B120 travelall, and I really like it. Since the
engines all use the same brackets, I just swapped the generator and bracket
and motor mounts onto the 304 and didn't bother to rewire or anything.
Clutch and flywheel is the same, too. Very easy swap except for the 40 years
of crud that covered up one of the engine to flywheel bolts, causing me to
say many bad words at first, and laugh at my own stupidity later.  I'd
already swapped 304s to 345/392s and knew better.

-Allan