Bellhousing Alignment Tech & Tips

[@mikeheggem9488]

Another thing to take into consideration when having block at machine shop is to have them machine back face of block to square up to crank centerline. Mine was out 8 thousanths.

[@laserdad]

I'm so glad that you took the time to document this procedure. I've watched several alignment videos, but yours is the first to mention that the face has to be aligned.

[@rosswesner2531]

Thanks Jeff, just did this procedure on my 66 Nova with a Tremec 5 speed. The dial indicator set up took forever LOL. There should be a video just on that. One more task completed on a 20 year project. Next getting the hydraulic clutch installed and bled.

[@TaekwondoFitForLife]

Best explanation of concentric check!❤ loved the fact that you included the importance of both planes of alignment, both parallel to block face and of course the driveshaft check too, perfect and thank you for this! “Perfect explanation Sir”😊

[@PaulE.Fredette-bq1zg]

Something I Didn't Know. And You Made It In Eazy To Understand. As well telling Us About Rob MC adjustable dall pens.

[@trunkmonkey9417]

For those that have asked. All bell housings need to be checked, factory and aftermarket. It is 50/50. It either will be in spec, or it will not. But you have to be 100% certain. I put a TKO in one car, (years ago) and a TKX in the other this past year. One had an aftermarket housing (Bendtsens) and the other was OEM. Making sure all paint etc. is removed from the mating faces of the block, bell flanges engine and transmission sides, and the face of the transmission case. Also make sure the inside of the bell flange circle is clean, as well as the pilot bearing retainer outer diameter. And the dowel pin holes in the bell housing are clean and true. Running a fine tooth flat file (using fingertips like playing the piano) and make the file in figure eights or a knife stone like in the video. Also checking runout on the flywheel since you are already familiar with the process. Stacking up by using a clutch alignment tool, put the tool in the disc, put the disc in place flat against the flywheel, set the pressure plate against the clutch disc and install the pressure plate bolts and then run them down until the bolt heads just contact the pressure plate, and then tighten them in a star pattern about 1/2 turn each until snug (about 10 foot lbs) and then use a torque wrench set at 15 ft lbs, tighten following the star pattern and keep adding 5 ft lbs until you reach final toque per spec for your bolts (ARP) or per manual for your application. All of this will take some time, but worth every second you spend prepping for the miles and time you would be driving without troubles. And the RobMC cammed pins are worth everything they ask!

[@dohctorzc]

Best video on this topic period!! Thank you for the simplicity and common sense approach!

[@onemoremisfit]

According to what it says in my GM service manual, the oil pan on the LS engine is a structural member. It's easy to understand why they tell you this when you see how the bottom of the bell housing is bolted to the back of the oil pan as well as the top of the bell housing being bolted to the engine. If your oil pan is protruding and tilting the bottom of your bell housing out .03" then you have a misaligned oil pan. I can see how somebody might be inclined in a pinch to just remove metal from the rear of the oil pan to fix the problem, but the correct repair is to R&R the oil pan. I recently had the LS1 engine out of my truck and had to replace the oil pan. The GM manual says to use a straight edge and feeler gauge to align the rear of the oil pan with the rear of the engine. I found this was too difficult with the tools I had to get a true reliable reading, so I supported the engine in a manner that allowed me to bring the automatic transmission on it's own wheeled jack support to the back of the engine, and bolted the trans to the engine. Then it was easy to fit the oil pan flush to the trans bell housing the way it is supposed to be. Of course with an auto trans there is no input shaft location concentricity to check, but it's still important to have the back of the oil pan flush with the back of the engine no matter what transmission you mount on it. The GM manual says the rear of the oil pan must NEVER protrude, but even if the oil pan is not interfering with the bottom of the bell housing, you still don't want any large gap there either. A gap will cause things to flex when bolted tight. GM's specification says to hold the clearance from zero to .01" (.25mm). If you fit the oil pan flush after bolting on the bell housing, you have zero.

[@domenicscarfo1866]

Excellent video thanks only had to do this one time before to make sure the bell was centered but i did not check for flatness that os a good tip keep up the good work.

[@paulhiggins322]

Thanks Jeff & Cam for all The Cool Videos 👍

[@johnbehneman1546]

THANK YOU SO MUCH!!! GREAT VIDEO AND EDUCATION JEFF!!!! I LEARNED SO MUCH. PLEASE CONTINUE TO SHARE YOUR TRUTH.

[@terrybancroft5358]

Thanks Jeff was having major problems with bell being way out that tip about the LS pan hitting was the problem .

[@bill3641]

My dad bought a new Ford pickup in 1967 . The Ford dealership replaced the clutch do to shifting/dragging problems twice before one of the techs checked the bellhousing and found that the bellhousing was apparently drilled out of alignment . You never know ............

[@briankinchsular1313]

Thank you for being clear an concise. a lot of great info.

[@howardrodner2302]

Good info. Thanks, Jeff!

[@davidpoland7862]

Great info again guys. I’m sure a lot of people (like me), don’t realize how important this is especially with newer transmissions. And then there’s shimming hydraulic throughout bearings. Hmm, sounds like another video to me.

[@johnnyhotrod]

Excellent tutorial,thank you!

[@t.s.haynie4197]

Excellent video with great info

[@timgroleau1612]

Excellent. Explained well,

[@ArthurSperotto]

Excellent presentation!!

[@kenstubbert5483]

Keep It Coming Jeff👍👍👍

[@KSIXRIDER]

Great video, thank you.

[@ourbusyacres]

Thanks for the info, great explanation. I'm getting ready for a TKX install on a 02" LS6 for the 69 Camaro and wanted to know a reliable indicator and what I should expect to pay for it?

[@keithfilkins2043]

Thanks Jeff

[@BKMDano17]

Jeff, I put a tremek behind a 460 years ago and it never did shift properly. I think it's a combination of being off-center and the pivot ball not being long enough. Not sure the shop set this up and maybe they made a mistake. Anyway I'm building another one have a 460 block in the shop ready to go and I'm going to look into a quick time bellhousing I used the Lakewood last time. Thanks for the videos I'm a new subscriber keep them coming especially if you do any 460 stuff!

[@jeffsmith2003]

Thanks Dan - my experience with the older Lakewood bellhousings on small- and big-block Chevys was that they tended to be off my between 0.025 and 0.030-inch! So that may be why your trans never shifted properly. And as we showed on the video, then engine can represent part of that inconsistency.

[@faronmitchell6702]

Should a factory bell housing be checked? I keep having problems with clutch shutter taking off in first gear. New clutch set and flywheel. The car shifts great.

[@MoyaMotorsportsRacing]

Good video; we are familiar and use that process. However, when dealing with a GB where the bellhousing and main GB housing are all one-piece, is there a method, other than measuring the block and GB separately on a CMM machine?

[@Luis-tj4mc]

Bnm

[@andy347495]

are you ever going address indicator sag and how it affects the true indicated runout?

[@honestjohn9905]

Nice job.

[@joepaquette7435]

Any link for Rob mc for the dowels?? Nice video.

[@bobrl01]

Does the offset throw the bolt holes off bell housing and block

[@Danno74Z]

I think this post is dead. There is enough clearance within the bolt holes to allow movement. If you take a bolt and put it in a the bellhousing tons of clearance hence the need for dowel (alignment) pins. Have them on cylinder heads for the same purpose.

[@andy347495]

how come you didn't show the indicated run-out afterward?

[@reloadingfun]

If you want to stumble across some more info about using a indicator in this type of scenario, read the rest of this. You're missing one variable that a lot of people aren't aware of, even machinist I work with thay have been machine for 40+ years werent aware of it and that's indicator stand sag. If your indicator stand isn't ridged enough it will flex from the gravity. The stand you are using probably isn't ridged enough when the indicator is out that far. If you want to test it, attach the mag base to a bar stock or even some 2" square tubing. Zero the indicator then rotate it upside down and look how much the needle moves.

[@curtthompson2787]

How do you orient the gauge to know that its exactly centered with the crank before starting?

[@jeffsmith2003]

Curt - thanks for the question - that is something I probably should have addressed in the video. The beauty of this procedure is you do not have to center the dial indicator. Merely place it so that it will read consistently for the entire 360 degrees of rotation. This will take some time to set up but once the dial indicator is positioned all its really doing is indicating the relationship of the housing bore relative to a stationary position of the dial indicator housing - since the dial indicator housing is not moving relative to the bore. When the housing bore is centered- the inidcator travel will not move away from zero. This is rarely the case, so the indicator reveals the position of the housing in relation to the indicator - that's why it's important to keep track of which way the indicator moves - in or out - so you know it's relative position to the crank centerline. Hope this explanation helps. Feel free to ask more questions!

[@YZFoFittie]

How does a 7 thou dowel move the bell 14 thou? I can't get my head wrapped around it!

[@mtd610]

How to you true the micrometer to the crank? If the mic isn't centered to the crank wouldn't it throw off your measurements?

[@jeffsmith2003]

Yes you are correct - if the dial indiator is not pependicular to the surface, it will affect the reading but sometimes it's just too time consuming to get it square. I've checked it both ways and frankly can't see a significant difference - perhaps 0.001-inch. If you are concerned with total accuracy - then yes it's important- but with a spec range of 0.000 to 0.005-inch - an error of 0.001 isn't that critical.

[@Danno74Z]

You said at the beginning of the video one has to be within .001" inch of concentricity - FALSE. One has to be with .005" run out or .010" of total indicated run-out. So if one has a reading of 8 thousand on the dial indicator their run out is 4 thousand and within spec and they don't have to do anything with offset dowel pins.

[@Saan455]

First like

[@johnbehneman1546]

TAKE YOUR TIME. DO NOT RUSH.