Impromptu Overhaul

[edwardc]

Be sure to remove both of the ¼-20 Allen-headed set screws from below the spindle before attempting to pull the spindle.

Here and here?? (see pic) No knowledge, just a guess.

There's cretainly enough meat in the casting there to hide two setscrews at the bottom of long bores. I'd say that would qualifiy as a "Booby trap".

[GregH]

yeah I think the right hand hole you marked in the pic Ed is going to need some better light and gentle exploration!

[jcwright]

I've checked my notes and photos, but the details I was hoping to find on the 2 set screws are not there. IIRC, the 2 screws are in the *same hole*, set one on top of the other. Someone please correct me if I've misremembered.

j.

[W2ET]

From Don:

Yes, the idler gear shaft is indeed difficult to remove and replace. The first booby trap that you'll encounter is that there are 2 (not one) quarter/twenty Allen-headed set screws in the same hole which will be holding the shaft in place from below.

Most machine shops seem to be able to safely pull and replace the shaft if it needs machining, but please resist the temptation to simply pound it out from the crankcase side of the block. To do so not only damages the inside end of the shaft, but risks cracking the block. We recommend removing the shaft to be re-machined any time that it is noticeably scoured. Otherwise, the bushing (even a new one) will quickly wear excessively.

In terms of a specification for the brass bushing to shaft clearance, our machine shop tells me that a standard ASTM clearance for that type of bearing would be .002. However, Universal recommended a wider clearance (up to .004"), so that a generous amount of oil would flow past the bushing and work its way out to the outer edge of the idler gear to be "flung" over to the small catch basin in the rear face of the accessory drive. You can read more about this system of providing oil for the accessory drive in a Tech Tip on our website called "Accessory drive repair and modification".

As a summarizing note, we have seen many idler gears and shafts come into our shops with quite badly worn shafts and bushings, and while we know that loose idler gears can create quite a "clicking" sound at low RPM, we have never heard of a gear or shaft actually failing in service.

[GregH]

There it is!

Ok.. more careful looking and found the idler spindle set screws! For future reference.

[GregH]

Since the block is going in for testing and cleaning, I assume ALL the plugs and such nèed to be removed yes? Like the ones in these pics?

[Al Schober]

Yes, remove all those plugs. This will give you or the shop access to the passages. Use similar weapons for cleaning as are used for a rifle barrel - wire brush on a long thin rod.
Original plugs have a cross slot. I changed to plugs with a recessed hex (they take an allen wrench).
Oh yeah, be sure the camshaft bearings are removed before they hot tank the block.
When you get the block back, I recommend you change some of the original fasteners from bolts to studs with nuts. I've done this at the water jacket cover plate, the tappet cover plate, and the carb attachment to the manifold.

[GregH]

Yes, remove all those plugs. This will give you or the shop access to the passages. Use similar weapons for cleaning as are used for a rifle barrel - wire brush on a long thin rod.
Original plugs have a cross slot. I changed to plugs with a recessed hex (they take an allen wrench).
Oh yeah, be sure the camshaft bearings are removed before they hot tank the block.
When you get the block back, I recommend you change some of the original fasteners from bolts to studs with nuts. I've done this at the water jacket cover plate, the tappet cover plate, and the carb attachment to the manifold.

ok that makes sense!

What is the best way to get the cam bearings out? Piece of wood the same diameter and gently tapping with a mallet?

I like the hex plugs idea!

I was thinking about that for the water jacket cover plate, but will do it for the others as well.

[GregH]

Cam bearings

good advice from Don of course!
answered my questions about the cam bearings.

https://www.moyermarineforum.com/forums/showpost.php?p=18085&postcount=7

[W2ET]

Memo to self:

When "A" is below "B" with the engine right-side-up, "A" is above "B" when the engine is upside-down.

Duh....

Bill

[GregH]

Hot Tanking

When they do this at the shop, does that process work to flush out the fine rust sediment that has built up around #4 cylinder and the end block wall?

[GregH]

When people have had their block hot tanked/cleaned, have you also have them do the oil pan and transmission case?

If yes, how best to get the shifter cross brace out before hand? Or does one just leave it in?

[GregH]

Head Studs

The pics are of the head studs. The threads look like they had pliers used on them before I got the boat. Are these good enough that I can run a die over them to clean up the threads and carry on ?
The second pic is of the thermostat cover studs. On the right hand one there is a groove about 1/2" long on smooth body of the stud. This looks to be the area that would sit in the sleeve of the thermostat housing. So would it be ok?

[Al Schober]

Hate it when folks do that! That's exactly why the Snap-On stud remover is such a nice tool.
I think you'll be fine if you run a die over those threads. On reinstall, don't use a pipe wrench. At least, just jam two nuts together to seat the stud in the block. I install to 35 ft-lb - if there's a problem, find it as early as possible.
After the head is in place, use some lube on the threads and between the nut and washer. I use the silvery anti-seize from Permatex. Some black moly grease would be an alternate. Anything is better than nothing.

No need to tank the oil pan or transmission housing. Personally, I recommend changing the reversing gear cross shaft with the stainless one from our host. Do those two seals as well as the aft seal while waiting for the block.

[GregH]

Idler Spindle

The Moyer idler spindle remover worked like a charm. But, ummm, how do I remove the threaded portion from the spindle? I can't back it off with just hand pressure and I don't want to use anything that would damage it.