Ed's 77 Terex 72-41

[mountainguyed67]

I got home in time yeserday to get the steel and tooling I need to build the turbo flange, before the places closed.

 

[mountainguyed67]

My main concern last time was getting it lined up so the flex plate bolts can go in, since I forgot to do that before stabbing the engine. The flywheel was lined up with the access hole in the bell housing, but the flex plate behind the flywheel was lined up with the only unthreaded hole between two of the eight threaded holes (happen chance). I tried reaching past the flywheel through the starter hole with a welding rod (the only thing that would fit), but it just bent when trying to move the flex plate. So we put a screwdriver through both flywheel and flex plate, and turned the crankshaft by hand as much as possible. The holes were centered on the access hole to start, so we could only move it about 3/4” to 1” the first time. Then we removed the screwdriver and turned the crankshaft by hand to the next hole, and stopped as soon as the hole got into the access hole. That way we could move it as much as possible each time. The screwdriver went through the flywheel, but not the flex plate.


That’s what we wanted. If the screwdriver went through both, it meant the flex plate wasn’t staying put back there, it was being drug along with the flywheel. That would have been a bad thing, meaning we needed to separate the engine and transmission again. So now that the holes didn’t line up, the screwdriver was put through the flywheel and pushed against the flex plate. So the flex plate would move along with the crankshaft. Then the crankshaft turned again, until the screwdriver was against the access hole. Then the screwdriver removed, and crankshaft rotated to the next hole again. After doing this a few times we were convinced the flex plate hole was within the access hole, but of course we couldn’t see it. So we looked for it as soon as the flywheel hole got into the access hole, by pushing the screwdriver in. It wasn’t there. So we rotated the crankshaft just a little, and pushed the screwdriver in again. There it was, hallelujah! Then we put in a bolt, but it was pushing against the face of the flex plate. This meant the holes weren’t quite centered on each other. So we put in a bigger screwdriver that just barely fit in the holes, and that centered them. Then we were able to thread a bolt in. We left that bolt in even though it isn’t the correct bolt, so the holes couldn’t get misaligned again.


My helper friend took quite a long time to catch on to what we were doing, even though I told him from the beginning that we would drag the flex plate along when rotating the flywheel, until the flex plate hole was accessible through the access hole. I explained it about four times. When we got to the part where I was convinced the flex plate hole was back there, he stopped and said “I don’t understand what we’re doing”. I made a circle with my thumb and finger and pointed close to the bottom, then said it’s not here. Then pointing a little higher each time, I said “maybe it’s here, maybe it’s here, maybe it’s here. Jab your screwdriver in and find it”. He said “Now I get it”. I had already told him to look with the screwdriver, not with his eyes. We couldn’t look at it straight on, and not close. So any sight picture we had that way was distorted.

 

[mountainguyed67]

The flange is done, my son is going to weld it on for me in the morning. I left .03” to clean up after welding.

 

[mountainguyed67]

Already tested hole placement.

 

[mountainguyed67]

We’re getting very close, last thing is to connect turbo to blower, and connector turbo intake to the filter.

 

[mountainguyed67]

No, I don’t like the exhaust where it is. That’s where the mechanic helping me put it.

 

[mountainguyed67]

Maybe some of you are better at Detroit Diesel part numbers than I am, need one of these that offsets right instead of left. It won’t clear the cab like it is.

Mechanic wants me to find someone to cut it off and weld back on the other way, it’s aluminum.

 

[spitzair]

Can you turn the turbo around 180 degrees so the exhaust is at the back and the intake at the front? That way you get the exhaust away from the cab and maybe use the air intake you have? Just a thought...

 

[mountainguyed67]

Can you turn the turbo around 180 degrees so the exhaust is at the back and the intake at the front? That way you get the exhaust away from the cab and maybe use the air intake you have? Just a thought...

We looked at it that way first, I forget why it wouldn’t work.

 

[mountainguyed67]

No, I don’t like the exhaust where it is. That’s where the mechanic helping me put it.

By this I meant I want a 90 going back, that’s how he had it set up originally.

 

[mountainguyed67]

We got the part above cut and reversed, then found out the charge pipe needed to have an angle at the turbo end. He showed up today with the modified charge pipe, but it was too short. He hopes to have it right tomorrow. We got the new fuel filters installed and pushed fuel to the engine with air pressure. Also filled the steering hydraulic tank.


Yesterday’s pictures.

We moved the air filter from the back corner, to the hood. Routing is easier, and the mechanic says you don’t want the filter in the back corner on a Forest machine. You’ll clobber it. We had to do some cutting and drilling.

 

[mountainguyed67]

We got it started, but it had three leaks; radiator, compressor air line, and a hydraulic line I had off and on when plumbing in the valve to run the log grapple. We took all that off and are coming down in the morning, I want to get to the radiator shop before it closes. It seems to run good, and the steering and bucket still work. There was a problem with the steering before, maybe my cleaning the pickup screen inside the tank fixed it. I hope so. I’ll load video when I get home.

 

[kshansen]

We moved the air filter from the back corner, to the hood. Routing is easier, and the mechanic says you don’t want the filter in the back corner on a Forest machine. You’ll clobber it.

Well looking at those pictures it looks like he was a little late in mentioning that! Looks like it took a major hit already! I'm assuming he inspected it inside to be sure there was not going to be any unfiltered air getting to the engine?

 

[mountainguyed67]

Looks like it took a major hit already!

It was that way when I got it, I’ll try to find a good one.

 

[mountainguyed67]

I'm assuming he inspected it inside to be sure there was not going to be any unfiltered air getting to the engine?

We both did, it’s good.

 

[mountainguyed67]

 

[mountainguyed67]

 

[59 North]

We both did, it’s good.

Just a question, is there a difference in the air filter element, [P/N], between a turbocharged and non-turbo'd engine?
For the same air cleaner housing.

 

[mountainguyed67]

I don’t know, it didn’t occur to me that it might be.

 

[Welder Dave]

I think air filters are based on CFM requirements of the particular engine but I'd guess most don't come with the absolute minimum requirement. I think the Baldwin catalogue has a listing of the CFM requirements of popular engines and their air filters. You could compare turbo to NA and see if there is much difference.
Who gas welded the intake pipe and did you test it for leaks?