B-73 Restoration

[Freightrain]

I think most of the painting inside is for rust control on engines/machines that may sit for long periods of time.  A daily driver will not see any advantage.

I've heard it helps with oil drain back?  I think that is an old wives tail.  Once an engine is running, everything is coated and the oil will drain back fine no matter what.  To each there own I suppose.

 

Like any other paint, it needs put on properly or it could fail and come off.  That won't help anything!

[mrsmackpaul]

I was told the painting of castings was to stop oil seeping thru possible porous spots on castings

This was on big industrial gearboxes, is in drives maybe 4 feet high

I assumed it was correct what I was told

However after reading freight trains comments I am wondering if I was fed a line as young gullible person

The reason I say this because the inside of my Macks fuek tanks are painted with red stuff like the block 

That block looks amazing, what is this dremel flexible head wire wheel doohickie mentioned, it does a impressive job as did the hand holding the dremel thingy 

 

Paul

[mowerman]

Yes, I was wondering the same thing. Once I start doing my bodywork I will be looking for anything that would help out with hard to reach areas.

[h67st]

Flex shaft is an attachment that chucks into your dremel, then you can put a wire wheel or whatever tip you want in it.

[mowerman]

Aaaaaaaaaaaaaarite thanks for that

[mowerman]

Ha ha that one thing looks like a dental tool

[1961H67]

It’s a must for restoring, cleaning  on engines ,, get a kit, it has a lot of attachments , wire brush’s , grinding stones, cutting wheels. 

[mechohaulic]

and they work real well in model building . also shortens the list of "to do items" getting things done faster.

[Freightrain]

I remember my Dad buying a dremel back in early 70s.  I still have one that is about 25 yrs old.  It quit turning one day, I pulled it apart to find a nylon bushing that attached the motor to the chuck.  Found replacement and was back in business.  New dremels are crazy expensive and many are variable speed like mine.

[mattb73lt]

I got this one from my Dad's shop when I closed it up. It sat for a long time, but I find it indispensable now and it gets a ton of use.

And Larry I'm with you on the Glyptal. Not sure if it's really worth the effort of applying it with its return. I had several people recommend it and with the condition of the block, I figured it was worth it.

The Dremel got another workout cleaning up the crankshaft to a condition that was acceptable for assembly. The crankshaft just fit between two dead centers on the lathe with only about three inches to spare. It made turning it easy for the cleanup. You can see in the last photo the flanks of the counterweights needed some serious cleaning.

[mrsmackpaul]

Thanks for all the info on the dremel

Do wrap a bit of tine around the crank journals a hold them on with a hose clamp incase you slip with tool while cleaning it up

Would be a shame to send it back to the machine shop

Im sure well over whats going on and Im no expert motor builder,  not even a amature one really 

Lathe is just big enough, it is amazing the way we use tools we possibly never thought we would of 

Great work and thanks for the up dates

 

Paul

[mowerman]

Excellent… Bob

[mattb73lt]

All cleaned up. .30 cal and 5.56mm bore brushes plus some Viet Nam era rifle bore cleaner got the oil passages shiny bright. The Dremel has the exterior looking as new. I think it’s ready.

[Joey Mack]

that crank looks really clean..  You are inspiring me..  Jojo

[mowerman]

Wow, that’s amazing. It looks brand new… Bob

[doubleclutchinweasel]

We used to paint all the interior surfaces on out "hot rod motors" with Rustoleum.  Sealed everything and made the oil drain back faster (or at least that is what the rumor was).

Beautiful work...as always.

[Vladislav]

I wonder how did you put the shaft onto the lathe? That thing is supposed to be damn heavy. We have to carry Mack cranks by two men and when I took the last one off a block I just hooked a chain hoist to it. 

The final result of the cleaning looks tasty. 

[mattb73lt]

3 minutes ago, Vladislav said:

I wonder how did you put the shaft onto the lathe? That thing is supposed to be damn heavy. We have to carry Mack cranks by two men and when I took the last one off a block I just hooked a chain hoist to it. 

The final result of the cleaning looks tasty. 

Just used my engine hoist and a two short straps to get it on there. And it is damn heavy!!

[Vladislav]

3 minutes ago, mattb73lt said:

Just used my engine hoist and a two short straps to get it on there. And it is damn heavy!!

And still not easy task if nobody's helping out from aside 

[mattb73lt]

I'm not super clean, but I was taught to rebuild engines as clean as possible. Some shops I've been to, like the one I just used, leave a lot to be desired and it's a reflection of what their product will be. Even with this shop, which is the last one in my area that can handle parts this big, I had some issues. These parts definitely needed extra elbow grease to make them usable again. As long as the machine work is good and accurate, I don't mind doing the dirty work. There was no way I was going to assemble this crank into the block without some extra cleaning. I'm also not going to pay someone for something I can do. Here's how it came back after some work and being hot tanked and what it's like now, showing the same spot in both pics.

[Mark T]

Give those journals a little polish job before you're done cleaning.  Don't let anyone talk you into any bearings other than tri metals.  

[mowerman]

As time goes on everything gets worse I was going to do brakes on the old lady’s explorer… but I don’t even know anyone around here that turns rotors these day I just sent it to our trusted repair shop I remember years ago they would acid dip all machine parts before they even started 

[mowerman]

Cylinder heads in my area I recall they were look brand new when they got back from the machine shop cut corners. It’s the name of the game these days if you can find anybody to work them at all good luck ha ha…. Bob

[mattb73lt]

I did not have a good week with this engine last week. After getting the crank cleaned up they way I wanted it I was convinced the shop I went to did not do any polishing to it. Close inspection revealed that the journals appeared to be in the same condition as when I dropped it off. I was able to get Rocky to come to the shop last Wednesday to look it over with me. We remeasured every journal in four spots and all were within .0008" to .0003" of the undercut it had been given during its last rebuild and well within tolerances for heavy polishing. The week prior I contacted a guy I worked for in high school and sent him pictures of areas I had concern with.  He was of the same opinion as Rocky, that it hadn't been polished. Rocky wasn't happy with any of this either and this was from a shop he'd recommended. He told me he felt bad about sending me there and wasn't comfortable putting this crank into the engine. I had my reservations of this particular shop and voiced them to Rocky before anything left my shop. About the time I contacted my old boss I was shopping for another place to go to. I received several recommendations. I did talk to Tom from Mahoney & Son in NH that week, too. He strongly recommended the shop they go to in Malden, MA. So last Thursday I loaded up the B42 with both crankshafts and hit the road early to make my way through Boston to Malden. Friday, I went to the shop in Hamden and removed the two sets of heads and parts I had there and brought them to Malden as well. The conversation at that shop was not pleasant, but I was professional and adamant that I was through doing business there. As I was leaving the owner did hand me back $1K in cash for the work he didn't complete. Luckily, he hadn't assembled the new parts into the heads before I removed them.

So some set backs and time lost at this shop, but I want the work I'm paying for done right. I don't want to have to do this again. I should've gone with my gut instinct and stayed away from this shop. It is getting so hard to find a reputable shop nowadays in my area. The new shop is a Cummins and Perkins Certified shop and the owner took me on a tour when I arrived. It's also about a two hour ride from me. Driving the B42 through Boston on I90 was a trip and a half. The WAZE app on my phone was my navigator there and extremely helpful. On the way back I stopped in Framingham to have lunch with my brother. That rarely happens due to our jobs and the last time we did, I was still a Trooper.. He's a civil engineer for JF White Construction and has done a lot of bridge, tunnel and rail work in his career around Boston. He was the project engineer on the Bunker Hill cable-stay bridge during it's construction. I had to break his balls that I was lucky to cross it in the Mack without it crashing down. Still moving forward after this hiccup.

[mrsmackpaul]

Well better to discover this now than later 

And you got to have lunch with your brother so thats a bonus 

 

Paul