Offshoreonly.com

Offshoreonly.com (https://www.offshoreonly.com/forums/)
-   General Q & A (https://www.offshoreonly.com/forums/general-q-20/)
-   -   Main bearing bore variance after line hone (https://www.offshoreonly.com/forums/general-q/292534-main-bearing-bore-variance-after-line-hone.html)

MER Performance 03-12-2013 07:14 AM


Originally Posted by blue thunder (Post 3883916)
Mer Perf, don't let stevexm get you going. He likes to debate and you will surely tire before he does. There really is no point and you will just end up POed for no reason. Pretty much what I was alluding to earlier. I surely appreciate you sharing your insight into the machine work tricks of the trade and would like to see it continue. A word to the wise is sufficient...

Thanks for the insight, I was already@ that point. I am not going to argue and lower myself. If my point is not understood or someone wants clarification; just pick up the phone and call.

Lets let Budman II, get back on subject of his thread.

Budman II 03-12-2013 02:38 PM

Update
 
Took the block to the machinist who worked on it originally on Friday, and he got out his Sunnen bore gauge and checked it with me watching. He measured it at 2.9375 or thereabouts, and it got a bit looser on the last couple of bores, but still within spec according to his gauge.

For grins I took it to another shop who is closer to my work - they do a lot of engines for local drag cars, circle track, and occasional truck pullers. He also used a Sunnen gauge, and measured it out on the small side for the first couple of holes - I believe he got 2.936 and some change. He thought that would be a bit too tight, and I will admit that I was concerned that I was showing around 0.0026 bearing clearance on the front two mains. His measurements showed it going large towards the back of the block as well.

I decided to go ahead and spend the money to have him line hone it again. He said he would take the very minimum needed to clean it up, so hopefully I will be able to avoid having to go with a smaller timing chain.

Going to check rod clearance while I'm waiting on the block. Hopefully I won't find any surprises there. It would be nice for something to go right on this build for a change. :picard1:

blue thunder 03-12-2013 08:42 PM


Originally Posted by Budman II (Post 3884513)
Took the block to the machinist who worked on it originally on Friday, and he got out his Sunnen bore gauge and checked it with me watching. He measured it at 2.9375 or thereabouts, and it got a bit looser on the last couple of bores, but still within spec according to his gauge.

For grins I took it to another shop who is closer to my work - they do a lot of engines for local drag cars, circle track, and occasional truck pullers. He also used a Sunnen gauge, and measured it out on the small side for the first couple of holes - I believe he got 2.936 and some change. He thought that would be a bit too tight, and I will admit that I was concerned that I was showing around 0.0026 bearing clearance on the front two mains. His measurements showed it going large towards the back of the block as well.

I decided to go ahead and spend the money to have him line hone it again. He said he would take the very minimum needed to clean it up, so hopefully I will be able to avoid having to go with a smaller timing chain.

Going to check rod clearance while I'm waiting on the block. Hopefully I won't find any surprises there. It would be nice for something to go right on this build for a change. :picard1:

FWIW, I rarely get away with just one set of main or rod bearings. In my experience if you want it right you have to tailor each individual journal fit to what you desire. So I wouldn't say things aren't going right for you, its just hard to get it precise and consistent across all parameters. Keep us posted on your progress.

Mer Perf, if it makes you feel any better I just rolled in the door from 15 straight hours of union negotiations (debating)..... It blows there too. :lolhit: But tomorrow we will go again. :angry-smiley-038:

Budman II 03-12-2013 09:36 PM


Originally Posted by blue thunder (Post 3884748)
FWIW, I rarely get away with just one set of main or rod bearings. In my experience if you want it right you have to tailor each individual journal fit to what you desire. So I wouldn't say things aren't going right for you, its just hard to get it precise and consistent across all parameters. Keep us posted on your progress.

I guess we will see where we end up when the block comes back. Hopefully I will be within a couple ten-thousandths across all the bearings. That should be acceptable, right? I have to wonder how many engines are running around out there with tolerances all over the place. Probably quite a few. Hopefully mine won't be one of them. Not thrilled with having to fork out another $150 to get this thing line-honed again, and I sure won't want to spend another $140 on top of that for off-size bearings. I have to draw the line on spending money on this damned thing soon. Starting to get some rumblings that work might be slowing down significantly pretty soon. At this rate I won't have any money left over to put gas in the boat to enjoy the new motor.

Budman II 03-18-2013 10:06 AM

Was measuring rod bearings last night and got 0.0029 on #5 and 0.0030 on #6. Remainder measured .0026 or .0027. The journal for #5/6 did not measure significantly smaller than the rest. Do I have a problem here? Wondering if I am going to have to have a couple of rods resized.

MER Performance 03-18-2013 11:47 AM


Originally Posted by Budman II (Post 3887595)
Was measuring rod bearings last night and got 0.0029 on #5 and 0.0030 on #6. Remainder measured .0026 or .0027. The journal for #5/6 did not measure significantly smaller than the rest. Do I have a problem here? Wondering if I am going to have to have a couple of rods resized.

You can buy, individual rod bearings. Get 2 H .001. Check 5&6 rods against 3&4 rod journal.

Budman II 03-18-2013 12:22 PM


Originally Posted by MER Performance (Post 3887651)
You can buy, individual rod bearings. Get 2 H .001. Check 5&6 rods against 3&4 rod journal.

I am going to measure the rod big ends, and compare them to one of the rods that are in spec for bearing clearances. What are the rod big end specs?

Thanks!

articfriends 03-18-2013 06:57 PM

Budman, what state do you live in? Years ago REICHARD racing in Owosso Mi did EXACTLY the same thing to a Merlin block I had except the front to rear main cap bores had a variance of .0025 from loosest to tightest . After being blown off on the phone I took block back to them, they kept it inside all day to measure it (was cold when I dropped it off) , I came back and they claimed they only measured it and there was nothing wrong.They really screwed me a second time, after that the mains were then also OUT of round because they re-cut the caps in a attempt to bandaid the mess they created, and stuck them back on. It took alot of pizzing around from my current machinist to straighten it out. I feel your pain on this, nothing better than having a machinist try to tell you that the resulting loose clearances would be good with disregard to the fact that all proper register/crush of the bearing shells would be close to nothing, Bob Madera summed it up pretty well, Smitty

Budman II 03-18-2013 08:14 PM

Thanks Smitty. I am in the Louisville, KY area. Block is with a different machinist - hopefully he will get my mains straightened out.

Budman II 03-25-2013 10:07 PM

The Latest
 
Got the block back Saturday, cleaned it up and blew out all the passages. Tonight I finally got the chance to torque the caps down and measure things. First I measured the bores, and got within .005 of the spec of 2.9375 across all the mains. Sounding good so far. So I proceeded to install the bearings and check the clearances on these. Now I am getting .0015, .0015, .0012, .0020 from 1-4. Gave up and didn't bother to measure the rear main as of yet. CRAP!

I guess I'll be hauling my block and crank back out to have him double check the clearances. If my measurements are in the ballpark, I am definitely too tight for a performance marine engine. So how is this issue corrected if I do in fact have an issue? Will I have to buy a set of thinner (more clearance) bearings? I don't want to cut on the crank journals if I can avoid that.

This just doesn't make sense. I am running the stock bearings and my main bores are all in spec now. The only thing that could be off at this point would be the main journals being oversize, but I was measuring 2.7493 across the front four main journals.

Temp in my garage was only about 40*. Could this be affecting my measurements?


All times are GMT -5. The time now is 08:08 PM.


Copyright © 2026 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.