JLG40F engine question

[dbris]

My JLG40F has a Wisconsin engine that has no ID tag. I believe that it's a VG4D or VH4D and it has a distributor, not a magneto. My question is, what's the timing supposed to be set to, and is it possible that someone has a scan of the engine manual? Thanks, Dave

[willie59]

Can't remember for certain, but I'm thinking the 40F used a VH4D. Seems I remember they had timing marks on the flywheel, may have to have the front cover off to see them. You could try contacting Wisconsin and maybe get some info. http://www.wisconsinmotors.com/index.html

[OFF]

It's a VH4D. I should have lots of those manuals laying around at work. I'll scare one up for you monday.

[dbris]

Thanks again guys, a service manual would be just the ticket! By the way, I got to looking a little closer at that Hi Drive valve that has 2 coils, and it's the same dump and bang-bang that's on the bang-bang side except the BB only has one coil (just a bang I guess). Turning them both on at the same time seems to work although the engine is so out of tune that it doesn't like the extra load. So now that everything else is working it looks like it's time to tackle the engine. Dave

[OFF]

Quickest way to tell the difference between a VG4D and a VH4D is by looking at the carburetor. VG4D has a sidedraft carb, VH4D is an updraft.

I'll be working on an E-copy of the VH4D manual, but please and make sure which engine you have. Just cause it 'should" have a VH4D doesn't always mean it does.

[dbris]

It's a side draft carb so I guess it's a VG4D. It is an old JLG40F so I'm not surprised that it's a little different. Dave

[OFF]

spec is 23* BTDC @ 2000 RPM

Now the hard part. Take the flywheel screen off. One of the vanes has an "X" marked on it. Paint that vane white or yellow. Standing in front of the enging looking straight on at the flywheel, on the edge of the fan housing at about 10:00 oclock there is a square mark. That is TDC. Hopefully your housing isn't rusty (most are). This mark is also the center line of the "V" of the cylinders.
3-7/16" down from that mark (towards 9:00 oclock) there is a round mark on edge of the housing. That's your 23 degree BTDC mark. Good luck.

And I'll get a copy of both manuals scanned in for "future" use.

[dbris]

Thanks OFF, I won't be out there until next weekend but I'll give it a look then.
Dave

[OFF]

Thanks OFF, I won't be out there until next weekend but I'll give it a look then.
Dave

You're very welcome.

Now, a real world proceedure for rusty old engines with no markings left.
Find TDC for #1 cylinder on the compression stroke. Mark one of the vanes, (what ever one is easy to get at around the hood of the JLG). Mark the shroud/fan housing beside your vane of choice. Measure CCW around the circle of the housing that 3-7/16" and mark that. Good to go.

[wildhorse trnr]

You're very welcome.

Now, a real world proceedure for rusty old engines with no markings left.
Find TDC for #1 cylinder on the compression stroke. Mark one of the vanes, (what ever one is easy to get at around the hood of the JLG). Mark the shroud/fan housing beside your vane of choice. Measure CCW around the circle of the housing that 3-7/16" and mark that. Good to go.

Thanks for the real world info, I have come across a few that are so rusty or have fins actually broken(concrete pumps).
Do you happen to have a number or name for someone that can bring the old magnetos back to life??
I have 1 that I need repaired and I have never attempted to repair one.

[old743]

Hi all...new here. I have an old 743 Bobcat with a Wisconsin V461D I'm trying to rehab. Came across this thread and was wondering if someone could post or email me any manuals or info on the engine

[VoodooMojo]

Give this a shot:
http://www.wisconsinmotors.com/support_repair_spec/54

I should have other additional information as well.
Let me know if you need more.

Welcome aboard!

[old743]

Thanks a ton, Mojo!! ...followed the link and downloaded the manuals. That should help a bunch. If you have additional info handy I'd much appreciate ANY tips or advice. I picked the 743 up from a friend of a friend who'd had it sittin around for quite a few years unused. Fortunately I got it pretty cheap, because it crapped out on me just after I'd finished digging the new foundation on a job. (lucky timing, sort of...although my client wasn't too happy about the hunk of heavy equip. broken down in his back yard) I need to dig into the hydro system and see if the main pump's putting out the correct pressure, but I figured as it's had issues starting and I know it's burning a bit of oil, I should make sure the engine is in the best shape I can get it and make sure it's putting out the most torque it's capable of. Currently it's running real weak... won't turn r/or/l well and can't even make it up a steep drive under it's own power. Bucket functions, but when the machine warms up it starts to struggle under load...I've got a lot of work ahead, but I'm stubborn and I'd rather not just scrap the old girl. That just seems like a waste of good steel.
Thanks again!

[VoodooMojo]

It sounds like compression is getting low. Give it a rebore, new pistons, rings and valves and she will be good for another 30 years!

[old743]

Thanks for the advice! Sounds like a compression test is a good place to start...It'd be great if I could keep her running for another 30!