Tuesday question: marine exhaust manifold.

[[486]]

can you just drill and tap another hole in the block to fit the bellhousing's misplaced hole?

 

[arse_sidewards]

can you just drill and tap another hole in the block to fit the bellhousing's misplaced hole?

There’s not enough meat there. It’s on the edge of the bell housing lip. I would have if I could have.

 

[arse_sidewards]

Yeah, definitly the block and not the bell. Note the nothingness behind the hole.

 

[87manche]

Just toss some big tack welds at it. You're never gonna need to take it apart anyway.

 

[arse_sidewards]

Got around to measuring for the rod bearing problem.

Journal was 2.499" which as far as I care is right on the max end of the spec which is 2.4989" with no identifiable taper or out of roundness.

The rod bearing as installed in the cap torqued to "good enough" has an ID of 2.498"-2.497" with no identifiable taper or out of roundness.

So that explains the problem. So now I gotta spend some time looking around for rod bearings that result in proper oil clearance. Do I just buy more rod bearings and hope for the best?

Haynes for a 460:

Mercruiser manual from earlier in the thread:

Bearings I have:

Bearings that came out of it:

 

[[486]]

measure the old ones you've got?
wear is clearance.

 

[arse_sidewards]

measure the old ones you've got?
wear is clearance.

Lol

 

[[486]]

that ain't too bad looking

 

[[486]]

I know for a fact the ones in my daily look worse, because I put them back in a few thousand ago looking worse than that.

 

[arse_sidewards]

My rod bores mic to 2.653, maybe 2.652 and tenths in some spots. The bearings I have mic out to .076-77 for the new ones and .073-.074 for the old ones It's kind of hard to get a trustworthy reading on when sticking the corner of a curved surface half way into a mic anvil so take that bearing thickness with a grain of salt.

These rods came off this engine so at some point they worked, probably.

OEM bearings are still available. I'm tempted to order up a set for $40 and see how they fit.

The bearings I'm currently using are a reboxed King CR816SI which supposedly have a .0760" width.

So I've got an extra thou coming from somewhere...

 

[Lbhsbz]

Do you have a rod bore spec?

Those old bearings look OK honestly...if they're smooth and things measure up OK, I'd use 'em.

 

[ironman_gq]

Can't see the copper yet on those bearings, I'd wipe em down to pull any embedded crud out of them and run em. Easy enough to replace later if you need to.

 

[arse_sidewards]

Found a better engine service manual.

 

[arse_sidewards]

Interesting pattern on the cam lobes. I'm not spending $200 on a new cam so this is going in regardless. Crank case and water pump seal area is straight fucked which is to be expected since the area between the seals is exposed to the air (via a weep hole) and on a boat that means saltwater. I'm going to sleeve it with a stainless speedi sleeve.

Speedi sleeve options are 99812 and 99087 which are both .4382" long so two of them should work. Don't really wanna spend $60 on sleeves though. Maybe I'll braze and grind it. I don't really have a good way to do that accurately though and stainless would be good here...

 

[cj3a]

Put a ball between the mic and the inside of the bearing to get the thickness.

 

[arse_sidewards]

Preheated in the oven. Turns out oil grime doesn't start smoking until somewhere between 400 and 500.

And burnt the tab in. I didn't like how many rods the starter pocket was gonna consume due to questionable fitup so I welded the corners and am gonna deal with the rest of it later.

I'll clean it up and mill it flat this weekend, maybe, if I run out of other shit to do. Supposedly it's "not machinable" but I don't think carbide is gonna give a fuck.

It's in the oven cooling down now. The "bake time" setting is killer for post heat.

 

[Lbhsbz]

Interesting pattern on the cam lobes. I'm not spending $200 on a new cam so this is going in regardless. Crank case and water pump seal area is straight fucked which is to be expected since the area between the seals is exposed to the air (via a weep hole) and on a boat that means saltwater. I'm going to sleeve it with a stainless speedi sleeve.

Speedi sleeve options are 99812 and 99087 which are both .4382" long so two of them should work. Don't really wanna spend $60 on sleeves though. Maybe I'll braze and grind it. I don't really have a good way to do that accurately though and stainless would be good here...

Meh...stick a washer behind the seal to put the lip on a good spot on the shaft.

 

[arse_sidewards]

Got new rod bearings in the mail. Installed in the rods they measured up 2.502x bore. Mercruiser book said 40 foot pounds on the rod nuts. Haynes said 45-50 for a 460 through MY1990 and 41-45 for all subsequent. Set the wrench to 45 and fuckin sent it. Turns beautifully.

Oh, and the old bearings measured up at 2.507-2.512 bore. Glycol makes a shit lubricant.

 

[arse_sidewards]

So, back to head studs. I looked more into the Brazilian diesel and it will work fine with spacers.

if I buy a kit for a 4cyl 256diesel I'll get a bunch of 5" long bolts (Reliance part# F87802206) that will just barely have room for a thin hardened washer under them to prevent galling and it will have 5 excessively long ~8" bolts (Reliance part# F87802207) that I'll cram some spacers under. I'd rather have a bolt that just happens to be 5.75-6" long though...

M92PV4U linked R88044 which is 6.25. I think combining it with R88043 (5.25") might be the ticket. Both of these come in the head bolt kit for a 4020

Frankly I'm just gonna cross shop all my options until I figure out which one can get on my doorstep cheapest.

 

[arse_sidewards]

Cheapest I could find was just shy of $70 shipped for 5x R62419 and R62418

Oddly, the price was different if I used the obsolete R6xxxx part numbers instead of the R4xxxx. Needless to say I bought the cheaper ones. I think there's a 50% chance I'm going to get my order cancelled with "sorry, out of stock".

 

[[486]]

what's wrong with the ones that came with the moedurr?

 

[arse_sidewards]

what's wrong with the ones that came with the moedurr?

Wrong length for aftermarket head, not enough thread engagement, like not even close.

 

[arse_sidewards]

Rod bolt lengths are 2.4165, 2.4155, 2.404 and 2.424 down the driver's side of the engine and 2.4155, 2.416, 2.416 and 2.425 down the passenger side. I measured the bolts on two spare rods I had lying around and they were 2.418 and 2.419. I'm just posting here for the record so when I have this thing apart next time I can measure and know if any stretched.

 

[arse_sidewards]

Anyone got any tips for getting sludge and rust out of an oil pickup tube?

I'm just gonna throw it in the ultrasonic cleaner with some gasoline and blow it out with air.

 

[Lbhsbz]

Anyone got any tips for getting sludge and rust out of an oil pickup tube?

I'm just gonna throw it in the ultrasonic cleaner with some gasoline and blow it out with air.

use white vinegar instead of gasoline in the ultrasonic

 

[arse_sidewards]

Got my head bolts in the mail.

Clearance is clearance.

 

[arse_sidewards]

Well that's not the right chain despite being the right part number.

 

[arse_sidewards]

Valve stems are sealed.

I spend the extra $5 to get metal clad because I'm a baller like that.

 

[[486]]

sprocket almost looks like it is for silent chain (flat sided teeth) instead of roller chain (radius sided teeth)

 

[arse_sidewards]

sprocket almost looks like it is for silent chain (flat sided teeth) instead of roller chain (radius sided teeth)

Roller chain came off of it. No idea where it went.

The older 460s use a silent chain. The newer ones use a double roller. The Mercruiser uses a double roller but the timing gear attaches to the cam in a totally different way. If I'm gonna break out the mill and "make it fit" then I'll run gears.

Older style 460:

Mercruiser:

Newer 460: