Simp's M920 build thread

[simp5782]

I'm guessing you are doing that put there on the road?? Truck looks great Wes.

Yep. Not too difficult. I can have everything apart in about an hour.

 

[290smallcam]

I like. Wish I had as many toys as you.

 

[Lukes_deuce]

What fan clutch do you recommend? I emailed with kit masters and they werent too sure which model would work for the 915a1 I had.

 

[simp5782]

What fan clutch do you recommend? I emailed with kit masters and they werent too sure which model would work for the 915a1 I had.

Kit master 102532 is the number I have. It is a no air type to engage


I've got an air engagement type if you need one. It works I just went with the no air default.

I've got a spare no air one but it needs a rebuild done. Kit masters offers the kit. I've got a few bendix ones that can be rebuilt as well.

 

[simp5782]

Repair ended up not being a blown head gasket but a blown out freeze plug in the rear head facing the middle head. Was a 3/4" size. Was able to get one locally. Had to have a gasket kit shipped in. Was able to pull the head and reinstall the rockers and Jakes and not have to reset the overhead.

Don't know why it blew. Low mileage engine so maybe it was installed wrong. Or just had rust around it and got hot and cold too much and blew.

Replaced most of my hoses with silicone and constant torque clamps while I was in there

 

[frank8003]

You been berry berry busy

|Are you still finding "crap in the closet" that You will now put to use?
..........................Must be one heck of a closet!

 

[simp5782]

|Are you still finding "crap in the closet" that You will now put to use?
..........................Must be one heck of a closet!

It's 2 whole spare bedrooms in my house

 

[swiss]

Repair ended up not being a blown head gasket but a blown out freeze plug in the rear head facing the middle head. Was a 3/4" size. Was able to get one locally. Had to have a gasket kit shipped in. Was able to pull the head and reinstall the rockers and Jakes and not have to reset the overhead.

Don't know why it blew. Low mileage engine so maybe it was installed wrong. Or just had rust around it and got hot and cold too much and blew.

Replaced most of my hoses with silicone and constant torque clamps while I was in there

Standard Day in Wes's Office

He gets more done in a few hours than I do in months on my trucks

 

[frank8003]

Standard Day in Wes's Office

He gets more done in a few hours than I do in months on my trucks

Large gorillas have large closets

 

[Valor]

Repair ended up not being a blown head gasket but a blown out freeze plug in the rear head facing the middle head. Was a 3/4" size. Was able to get one locally. Had to have a gasket kit shipped in. Was able to pull the head and reinstall the rockers and Jakes and not have to reset the overhead.

Don't know why it blew. Low mileage engine so maybe it was installed wrong. Or just had rust around it and got hot and cold too much and blew.

Replaced most of my hoses with silicone and constant torque clamps while I was in there

I hate when that happens! At least it wasn't too serious. A lot of work to just replace a freeze plug.

 

[simp5782]

Well been busy with everything under the sun.

Got AC installed with dual condensers. Pushing 32 degrees with 95 ambient temp. I have it setup to pull air from the cab inner channel. Holds 6.5lbs of freon.

Had another freeze plug fail on the same head. Different plug though and was easy to pop in and go on the interstate.

Upgraded to an HT4B turbo and pulse manifold. Had a new turbo fail after 1200mi and had to have another one sent in and put on. 35psi

Installed some little coolers i have had in storage for a fuel cooler, transmission, and transfer case.

Buried it few weeks ago in Virginia on a soft road. Was a fun job to get it out. Little digging and was able to use a rear winch and snatch block off a tree to winch me forward and over.

 

[simp5782]

Did a transmission swap from the CAT 7155 to an Eaton RTOO-14613. This is a triple OD unit. .85 .73 .62. Transmission has a pump in it for cooler and external filter setup.

Good size difference between the two transmissions.

Top speed of the 920 is 81mph. The chart shown below showing those top 3 gears speed.

Went with EZ Rider clutch parts. Decent prices. 1850ft lb unit.

Clutch part # EZ208391-93B
Clutch brake #B201-500BP for 2in oversize
Pilot bearing # AB197V
1810 FR output yoke # 6.5-4-3561x
1810/9c Morph joint - 5-324X

Rear transmission mount and brackets had to be moved forward a foot.

Used the pedal and linkage and pivots from a Pete 357. I can't get a very good push on the pivot points due to the angle so I may be going to a hydraulic clutch from a 2015 cascadia and using the clutch fork from a Volvo VNL. That whole setup is around $500. I did have to delete an air tank for the time being. This shouldn't be an issue since they added a tank for the CAT transmission anyway.


Was able to keep the same jack shaft and use a 9C1810 morph joint.


Transmission uses U shaft pattern so it will be a little different.

Went with a world American Air shift PTO #wa20-08-7005

Drive wise it lost some low end but it'll pull thru 75 easy with an empty 870. I might have to swap in a 55000 transfer case if I have issues in 1st gear offroad etc.

Got a little too dark for pictures but will get some once everything is buttoned up.

 

[silverstate55]

Nice work Wes!!

 

[NDT]

Somewhere it was claimed that the Rockwell SUHD rear end is problematic. I was wondering about that as my 916 had the pumpkin replaced in service. Do you have an opinion on this after running all these miles.

 

[Lukes_deuce]

I was hoping you were going to swap in a Eaton Fuller into one of your trucks! As always, you make it look easy. Im interested in your feedback on how it performs!

 

[simp5782]

Somewhere it was claimed that the Rockwell SUHD rear end is problematic. I was wondering about that as my 916 had the pumpkin replaced in service. Do you have an opinion on this after running all these miles.

It's bad 27k miles put on it since March 1st. I've haven't noticed any chattering other than with it buried and not letting it stop the wheel spin before engaging or disengage the power divider.

I've seen more broken axles in dump trucks than anything and a few quarry guys have said that they bust em up from a heavy load going down hill in a low gear and using the jakes on high and causes an axle to near lockup from the brake force. Big cams have the strongest jake from everything I've read and heard and I've been told never to use It on high unless empty.

Few instances of power dividers being locked it and a spring can being hung and snapping teeth.

I went with 75/140 synthetic fluid and I see Temps in the 160 to 180 range on both axles at 60 at 90k.

 

[simp5782]

I was hoping you were going to swap in a Eaton Fuller into one of your trucks! As always, you make it look easy. Im interested in your feedback on how it performs!

Few hiccups mostly just from PTO issues with the dual winches and their load and kicking off.

Fixed the shifter today to make it a quick disconnect using hydraulic fittings.

Finished the transmission cooler and spin on filter. I did put an air louve on the inside inner fender to bounce air behind it.

Used 5/8" fine thread U bolt stock to make the L bend for the clutch linkage.

 

[simp5782]

All the interior floor was redone. Used foam board insulation under the cab and double stacked for noise insulation as the RTOO can be loud in the OD gears. Used a thin bubble type insulation and foam board from home depot.

Hole in the floor was 16 x 16. Used some 3/16 aluminum plate to cover it with 1 in weatherstripping to seal down.

Braced the shifter rid and it seems to be working OK. Clutch is a 15.5" 10spring 4000lb plate load unit. Used a big arch type clutch lever and cut it down

Under cab fuel cooler with fan and transfer case cooler installed.

 

[pevrs114]

This is a fantastic looking truck, you've done some great work. What sort of stuff do you usually haul with it?

 

[simp5782]

This is a fantastic looking truck, you've done some great work. What sort of stuff do you usually haul with it?

Rescue HETs that lose most of their shoes when they were headed home.