Ironhead Lower frame rail clearance issues

[Zaelyn2019]

Hey guys, new to the forum. I got a 1980 XLCH basket case. Engine case and front down tube serial numbers match, but I am having major trouble getting the rear lower engine mounts to line up. There is a bump out on the right side lower engine case (near the oil pump) that is making contact with the frame rail. For the life of me, I can't see how this engine is going to mount with out part of the case contacting the frame. Any wise words would be of extreme help

[needspeed]

You've got a basket case that has the same numbers on the engine and frame. So the engine must have been in that frame at one time. If the rear motor mount wasn't replaced or installed wrong and the frame isn't bent you've got to assume that it will fit.

Here's a video showing a motor being installed. The motor shown is an older one without the "bump" that's giving you trouble and some of the parts in the front mount may not be exactly the same, but the order of assembly should be the same. Line up the rear bolts first but leave them loose while assembling the front mount. Sometimes a prybar under the front of the case lifting it slightly helps to line up the rear.

https://www.youtube.com/watch?v=rpAknl-2W24

[IronMick]

Originally Posted by Zaelyn2019

... I got a 1980 XLCH basket case...

I believe that 1979 was the last year for XLCH?

[Zaelyn2019]

Thank you, Mick and Steve. Yes, Mick, you are correct. My ironhead is actually an XLH. It's an 80, but it was actually produced in late 79. So I still have a 79 style case (still has the hole for the kicker shaft, it's just been plugged). I know the original owner well, as well as the backstory on the bike. He broke the bike down 20 something years ago to redo the top end and transmission, but discovered that the countershaft had egged out the case pretty good. He abandoned the project, and I picked up the pieces about 5 years ago.Really appreciate the info and the video Steve. I'm finally getting to the point where I can put her back together and get her on the road. Hoping for the spring to get her broken in.

[ryder rick]

I would urge you to NOT pry on anything, if you have to bend or flex anything you are placing huge stresses on the rear mount. The rear mounts have a history of breakage.
Most of which I believe is due to incorrect motor installation.

I mount the rear first as it is a fixed location, no wiggle room. However there is some wiggle between the mount and the motor so you may be able to shift that to a more favorable position by loosening and retightening it.
Note the order of assembly of the front mount plates, spacers, and washers. BOLT LENGTH IS CRITICAL!!!! You can break the cases with a long bolt in the lower position.
Bolt length is also affected by forward peg mounts if they are sandwiched. VTwin sells these bolts in both lengths.

Minimize prying or pulling anything into position with the mount bolts. I start at the rear and see how the front looks. Shift the rear to make the front better then button it up moving from the rear to the front then up. I have slotted bolt holes slightly as needed for best fit. If you put it all in loose and just tighten it up chances are good you will stress something bad.

I discovered a bent frame this way.

Don't run without an upper mount. Use a 7/16 bolt and 1/4" steel minimum for upper bracket.
The later models have 2 mounts, one on each rocker box and a strap between the cylinders.. VTwin.sells those kits too.

They don't call me Ironhead Rick just because I'm hard headed

[Zaelyn2019]

I appreciate it ryder rick! I havent even attempted the front mounts because I can't get the rears to line up. My biggest issue is this: at the very bottom of the case (the area that sits in between the bottom frame rails), there is a drain plug of some kind. I can find ZERO mention of it in the service manual. Unfortunately, this plug creates a cylindrical bump out on the side of that lower section of engine case. This bump out is contacting the inside of the right lower frame rail, preventing me from aligning the rear engine mount. As i mentioned earlier, the serial numbers on the case and frame match, so I know this engine came out of this frame. I am obviously making some kind of mistake that I can't see. Could some one start by telling me what this plug is? as I said, it sits INBETWEEN the bottom frame rails. It is NOT t]he transmission drain plug. I thought maybe it was a sump plug since it sits roughly behind (but lower than) the oil pump.[IMG]https://photos.app.goo.gl/dVPZAsYcoRwnya3P6[/IMG

[needspeed]

Perhaps I should clarify what I meant when I used the word prybar in post 2.

When the engine is set into the frame the top 2 bolts on the rear mount are usually the first to be put in. Sometimes it's helpful to gently move the engine into position with a large screwdriver or prybar to get the 2 bolts started. Thats it. No prying.

The plug is a 1/8 inch pipe plug. If you took it out whatever oil is in the bottom of the crankcase would drain out. There is a debate about whether you should use it as such. But you could.

When the engine is all in that part of the case will end up very very close to the frame rail. But you already know that.

I can't see your picture link.

[Monte03]

Poster, Are you trying to install an Engine with the Gerator Oil Pump into an early Timed Pump Frame? The Gerator Gen frames have Presses in Divot for pump clearance , on drain plugs Drill and tap the drain plug with a 1/8 pipe tap, leave the OEM plug in the case and use the 1/8” Allen Plug to drain oil

[Zaelyn2019]

Unfortunately, no. The frame and engine are serial number matched. I'm beginning to think the frame is just tweaked

[ryder rick]

Somewhere along your year the Moco offset the motor slightly to the left so the front mount plates were not flat. I believe the rear mount changed as well. If any of these parts were swapped, that may be the source of your trouble. Order of assembly is critical for front mounts.

They don't call me Ironhead Rick just because I'm hard headed