Bellhousing alignment...

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mopardude318

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I've never done it before, but I'll try and get it right. I wanted to figure out a way to make some kind of stand so I can get to the back of the engine. I've seen guys do it in the car and hanging from an engine hoist.

I made a little cart based off an engine dolly. There's 2 flats on the rear of the block where it could rest on the stand.

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What kind of dial indicator do y'all recommend?

There's the Dial Test type (lever arm on the side) which read a little more accurately.

Starrett 3809A DIAL TEST INDICATOR- 0-15-0- 1-1/4" DIAM.

Or standard type.

Mitutoyo Dial Indicator, 0 to 0.500 In, 0-100 2414S | Zoro.com

there's also different readings 0-15-0 or continuous.
 
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Daves69 Thank you. I found a similar fixture from Precision Machine. Let me know if I have it set up correctly. Maybe in the next few days I'll have some time to take the measurements.

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Daves69 Thank you. I found a similar fixture from Precision Machine. Let me know if I have it set up correctly. Maybe in the next few days I'll have some time to take the measurements.

View attachment 1715280931

That appears to be the correct way to set-up one of the measurements. But, you must also measure insure that the face of the bell housing is parallel with the face of flywheel, so the transmission is both square with the crank centerline and the transmission shaft centerline is in alignment with the crankshaft centerline. I don't see the picture of the set-up to check the squareness of the transmission mounting face.
 
That appears to be the correct way to set-up one of the measurements. But, you must also measure insure that the face of the bell housing is parallel with the face of flywheel, so the transmission is both square with the crank centerline and the transmission shaft centerline is in alignment with the crankshaft centerline. I don't see the picture of the set-up to check the squareness of the transmission mounting face.

How would I set that up? I've read some people put the magnetic base on the oil pan, turn the motor over and check the surface of the flywheel... is that correct?
 
It's resting more on the head of the bolt than the picture shows. Trust me, for what I need to do, it'll be just fine. ;)
 
How would I set that up? I've read some people put the magnetic base on the oil pan, turn the motor over and check the surface of the flywheel... is that correct?

No, no, the flywheel mount you've shown is used for both measurements. First as you have shown, you are measuring the position of the transmission mount "candle holder" hole. Second, you measure that the face of where the transmission bolts to around that hole is square with the flywheel/crank flange.

In other words, not only must the transmission be properly centered when bolted up to the bell housing, it must also not be cocked at an angle resulting in the crankshaft centerline and the transmission centerline not being perfectly lined up straight.

Yes, using a magnetic base on an oil pan will allow you to verify that the flywheel has no runout when turned.
 
I use a magnetic base and indicator, both from Harbor Freight. Just take one of the bolts out at the offset hole and magnet it right to the flywheel. No need to overthink it

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Mopardude318, I was looking for that tool and found one that looked similar from a place called Precision MEASURE. You said yours was from Preciion Machine. Is that the same place or what was thesite you got yours from and cost. The one I found was 75 bucks. Thanks
 
What brand are you using for offset dowels?RobbMC performance sells some nice locking ones.Used them on my lakewood and work great.Just thought I'd throw that out there
 
Yes, it was from Precision Measure 75 bucks. Sorry about that.

And yes on the RobbMc dowels, I will be using those if I can figure out what the hell im doing here. At this point I'm kinda lost... lol.

When I make on revolution on the engine the dial gauge needle I think makes 1 complete revolution as well. But I'm not sure yet. I gotta screw my head on tight for this one. Dammit.
 
Yes, it was from Precision Measure 75 bucks. Sorry about that.

And yes on the RobbMc dowels, I will be using those if I can figure out what the hell im doing here. At this point I'm kinda lost... lol.

When I make on revolution on the engine the dial gauge needle I think makes 1 complete revolution as well. But I'm not sure yet. I gotta screw my head on tight for this one. Dammit.

There's a small dial on the inside. that one should not be moving to the next number...
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Look at my little number, it moves about half way. I think. This video might be worthless.



After watching that, it looked like the Big gauge actually moves about half, then goes back the other way. LMFAO. Boy am I not too bright in this area.
 
Each revolution of the big dial is .100
Small dial tells you how many time it went around. Thats a 1 inch dial indicator
 
Yeah, something's wrong there. Is that holding device actually centered on the crank? I'd expect it to move less than to the 90 and the 10 if you start at 0.
 
Start with some preload on it. Make the little dial at say 2 or 3. Then zero out the big dial.
 
Okay. It has preload. This is what I have for measurements.

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Looks like I might need .21 offset dowels, bellhousing needs to move straight up? I am within .001" on left and right which is perfect.

Am I correct here?
 
Yes. You are headed in the right direction moving it up. Did the preload make it easier for you?
 
Come to think of it? You actually want to move it down that amount .21
 
Well it was already preloaded, I just kinda centered it up a little better and repositioned the dial indicator.
 
I'm going to recheck my math here. I'll zero the gauge at the -44 and work backwards to see if my numbers still add up.
 
Yes, double check, but it looks like straight down with 0.021, engine must have had a pretty good align bore at some point.
 
Okay. I double checked and I zeroed the dial at the top 12 O'clock measurement (-44). It reads exactly +44 at the bottom (6 O'clock) position. I'm getting exact repeatable results. I feel good.

Yea, Hughes engines built the short block, at least they did a good job align boring it.

.021 offset dowels should be here tomorrow.
 
Okay. I double checked and I zeroed the dial at the top 12 O'clock measurement (-44). It reads exactly +44 at the bottom (6 O'clock) position. I'm getting exact repeatable results. I feel good.

Yea, Hughes engines built the short block, at least they did a good job align boring it.

.021 offset dowels should be here tomorrow.

So, 0 at 12 o'clock and +44 at 6 o'clock?

That would mean the bell has to move .022" up I think. Makes sense with the negative number too, the original negative numbers shows the bell is closer to the gauge at that point, so it was sitting low. Re-zeroed so the zero is at the smallest distance between the gauge and the bell, it shows the bottom of the bell as being further away from the fixed radius, so again, the bell is sitting low.

At least if my thinking is correct...

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It's not, I have it backward here. Sorry! The "negative" numbers threw me.
 
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