Engine & Trans alignment

Thu Apr 19, 2012 11:58 am

I have broken another clutch and need some help with the engine and transmission alignment in a 184.
Original clutch - Replaced due to spline wear on driveshaft Nov. 2010 (replaced both clutch and driveshaft)
First Replacement clutch - New OEM from Dealer - Broke all the rivets between the clutch disk and the hub Sep. 2011
Second Replacement clutch - new OEM from Dealer - Broke all the rivets between the clutch disk and the hub April 2012

I think that I have the engine and transmission mis-aligned. I need some help understanding where spacers should be (under or over) engine mounts and transmission mounts. Currently, I have both the engine and transmission sitting directly on the frame rails. Any washers are either above engine mounts or below bottom of the frame rails. The driveshaft appears to line up higher than the transmission (I have to pull down on the driveshaft to get it to line up with the transmission).
I have had both the engine and the transmission out of the tractor and not sure if spacers were required for proper alignment.

Re: Engine & Trans alignment

Sat Apr 21, 2012 7:28 am

Make sure you do not have a broken frame. The weak point is on the right rear, 3 inches from the rear. Also, make sure your frame to trans member is not cracked. The member is the 10" piece of metal that your 2 lower front transmission bolts run thru-- There should be no spacers on these bolts, the member should be flush with the trans case.
Both of these areas break quite often.
There are no spacers under the engine, and do not believe there are any on the trans that would adjust the engine up or down.
Good Luck
Hamiltonbob :{_}: :{_}:

Re: Engine & Trans alignment

Mon Apr 23, 2012 7:59 am

Currently, the engine and trans is sitting directly on the frame rails. There are a couple of large washers (1/4" thick) that are on the transmission crossmember that have me questioning my re-assembly. Currently they are under the frame rails (between the head of the bolt and the frame rail)

I'll inspect the frame for cracks or unintentional bends. Anybody have ideas for a tool to check out the alignment? I am thinking that a laser boresight (for a gun) stuck into the pilot bearing or the clutch would give me a fairly straight line. If I then turn the engine over by hand the circle it creates should zero in on the center point.

Still needing more ideas and help. My mower is :sick:

Re: Engine & Trans alignment

Tue Apr 24, 2012 10:16 am

Joshua, I just sent you 9 pictures via regular email that should help you. Now that I re-read your post - I didn't have to send the pictures at all. The PROBLEM is that the rear cross member that holds up the transmission is supposed to mount UNDER the frame, NOT inside the frame. No washers between the crossmember and the frame.

This should immediately fix your problem. The drive shaft, universal joint and the creeper input shaft should then all line up.

I hope that this helps you, NJDale

Re: Engine & Trans alignment

Tue Apr 24, 2012 12:09 pm

I just gave my 154 a quick check and the crossmember is located under the frame, just as b52c130 says.


Re: Engine & Trans alignment

Tue Apr 24, 2012 12:18 pm

Thanks Dale, The pictures are exactly what I needed. I'll go check it out.

Re: Engine & Trans alignment

Sat May 05, 2012 5:50 pm

Outdoors, so what is the 'verdict' ???

Re: Engine & Trans alignment

Mon May 07, 2012 7:25 am

I put a laser pointer into the pilot bearing and used electrical tape around the laser pointer to make it fit tightly.
The laser pointer drew a circle around the center of the transmission when I turned the flywheel by hand. The pointer drew the same circle when I left the flywheel in one place and rotated the pilot bearing.
The laser pointer was not a high quality one so I am ok with using the average of the circle. This gave me high confidence in the engine to transmission alignment.

Since this is not the first clutch I've had break, I suspected that my installation procedure may be causing the issue. It is really difficult to get the pilot bearing and the clutch plate lined up correctly. This time when installing, I put the bolts in for the pressure plate but didn't tighten them down. Same with the PTO Pulley. I then put the driveshaft in and lined everything up before tightening the bolts down.
The installation went a lot easier than it had in the past.

I don't know if my install procedure will help, but for the benefit of others, don't tighten down the pressure plate bolts until after the driveshaft is in place. This fall I'll tear it all apart again and see if the clutch is still in good working condition. If not then I need professional help.

Re: Engine & Trans alignment

Mon May 07, 2012 7:42 am

I am still stumped regarding the clutch pedal adjustment. The clutch fork moves the throwout bearing just barely enough to disengage the clutch and also to clear the pressure plate so it isn't spinning when the clutch is engaged.
Any wiggle of the foot and the clutch is engaged. Any touch of the clutch pedal at the top and the throwout is engaged. This is a really sensitive adjustment.
Anyone else struggle with this? A couple of the linkage holes are worn slightly oblong and I have been thinking about having them drilled and bushed. Would this be a contributing factor to my struggling to adjust correctly?

I have already had the fork welded and ground to the proper shape (this was worn where it contacted the throwout bearing). The throwout bearing was replaced at the same time.

Re: Engine & Trans alignment

Thu May 31, 2012 6:29 am

Well I have eliminated another variable. It's not my installation procedure.
This clutch lasted 5 weeks. Can't keep going like this. I need some professional help with this.

Re: Engine & Trans alignment

Fri Jun 22, 2012 8:00 pm

Outdoors, Have you checked the straightness of the main frame rails? They are suppose to be dead on straight all the way from the radiator to the rear where the trans-axle mounts.

A very 'low tech' way of checking the straightness of either the top or bottom of the C-section frame rails is to just use a string. A strong magnet can be used to hold the loose end of the string to the rail as you pull the other end of the string tight.

I was out in Colorado a few weeks ago and finally got to mow with my son's 184 (usually all I get to do is to work on it). The clutch pedal felt and worked just like any other car/truck/tractor pedal.

I really hope that you find the problem with your clutch. Something is mis-aligned with the drive shaft and is thus 'flexing' the middle metal of the clutch disc and with the rotation this mis-alignment is 'fatigue' breaking the center of the clutch disc.

If the frame rails are straight, maybe you could find someone relatively close to you with a 184 and you could take a whole lot of pictures of that one and then compare them to all of the engine, transmission, and rear trans-axle mounts on yours to be sure that all of the brackets are in the proper places.

Good luck, NJDale

Re: Engine & Trans alignment

Fri Jun 22, 2012 9:58 pm

Outdoors, Is your 184 the same as a 154? I had to loosen bolts on this plate to mate the driveshaft to engine.
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Re: Engine & Trans alignment

Mon Jun 25, 2012 10:32 am

Got to spend some good quality time on the 184 this weekend. Before tearing down the rear end, I put the driveshaft back in with just the clutch plate on the splines. There was 50 thousandths of space at the bottom of the clutch plate when the top of the plate contacted the flywheel. They could contact flush with the light touch of a finger, but it still leads to a misalignment issue where the engine is higher than the creeper input shaft. Being suspicious and curious, also checked the flywheel to make sure it was true at the clutch. Had less than 5 thousandths of variation at the clutch face. 8 thousandths for lateral runout, but this was an unfinished surface (by the ring gear). Pulled the flywheel anyways to make sure there wasn't any trash between the flywheel and crank.

Pulled all the rear end sheet metal, toolbox, 3-point, etc. Removed the transmission and bull gear drives (rear axle) from the tractor.
Inspected the transmission mounting points for wear (slop). None of the holes were oblong or worn excessively, but I did note that the trans mounts to the frame in 3 places on each side and there are some allowances for adjustment if the bolts are loosened. If I put a 1/8" spacer in the front transmission mount to lower the front of the transmission, this makes the clutch line up correctly with the flywheel. I think (hope, pray) this should solve the issue.

Dale - Glad you got to play with the toy you have put so much time into! I did check the frame with a 4 foot level, and a laser level (for the longer distance). Frame is straight and has no cracks. Thank you for the pictures, during disassembly I checked a few of the pic's you sent to verify that it was previously assembled correctly. All matched ok.

Pat - The 184 is different in the engine to transmission mating, but alignment issues occur anytime a machine only has one u-joint.

I did notice that HamiltonBobsCubs has a creeper front support bracket, but I don't see anywhere that it could bolt to on the 184. The bracket looked flat and some kind of ears would be required to get it connected to the frame.

Re: Engine & Trans alignment

Thu Jun 28, 2012 9:24 am

Outdoors, It sounds like you probably will have solved the problem by installing that 1/8" spacer under the front of the transmission. If that makes the drive shaft a perfect 90 degrees to the face of the flywheel - that should be it.

.050" doesn't sound like much, but when you flex the center of the clutch disc 2,500 times a minute - that would probably be enough to fatigue break the hub out of the sheet metal center disc.

Good Luck, I think and hope that that solves your clutch problem for ever. - NJDale

Re: Engine & Trans alignment

Tue Jul 03, 2012 4:14 pm

Got it all back together again. Hopefully for the last time.
I should know in a few weeks if it is going to hold up.