High Output D8

[Mike Mc]

At the Woodland, Ca show last month I took a video of my buddy digging on my old restored D8.

http://www.youtube.com/watch?v=sI9yQo4SPyA

Also a video of the kids playing on it at the Santa Margarita, Ca show in 2010

http://www.youtube.com/watch?v=6kHHtRUVucw

If you like the video's please give it thumbs up so they move up the ladder. Thanks Mike

 

[jazzyjeffer]

Whats makes it a High output?

 

[Mike Mc]

jj, the high output is a dealer upgrade. They speed the rpm up from 900 to 1200 and increase the fuel. They also add a harmonic balancer and extend the hard nose 2" to clear it. Dual stacks and dual air cleaners to help it breath. It has extra bars running through the transmission case to help prevent the ring and pinion gear from slipping. Some say the transmission gear gear ratio's are higher to help it catch the scraper to help push it.

I found the old girl with #5 having a bent rod and out of round crank journal. So I turned the crank and rebuilt the entire engine. Ya it was expensive but I saved it from going to the scrap yard

 

[yblock]

what is the serial # ih or 2u.cliff

 

[Mike Mc]

yb, the serial is 13,128

 

[yblock]

cat serial for older d8 should be 1h then #S or 2u then #s,iwas interested as ther was a high output 13a series,was not aware of earlyer. thanks yblock

 

[WabcoMan]

yblock,

Not quite correct - Cat serial no breaks for the D8 are:
1H, 8R, 2U, 13A, 14A, 15A, 35A, 36A, 46A, 77V
The 1H was the original RD8 which they changed simply to D8 in 1937.
High output D8's were selected off the 2U & 13A production lines

 

[yblock]

I was trying to get the serial prefex asto my recolection the only high output was a 13a,tho may have bin a high output in later 2u,as with oilclutches later 2ues had oil clutch all 13as wher oil master clutch. also the english built d8s had different prefexes,

 

[WabcoMan]

yblock,

Late 2U's & 13A's were the "Hi-Output" machines (with oil clutch).

UK Built D8's = 22A, 68A, 66V

These are all conventional drive tractors.
They didn't start building D8's in the UK until after Cat had introduced the D342 engine, so all prior built machines with the D13000 diesel are USA builds

 

[Mike Mc]

You had to put a slicker on to start and run this old girl (1951) because it was pumping water and oil out the back stack. #5 had a bent rod and the crank journal was out of round. So we pulled the engine and gave it a complete rebuild. While I had the engine out we swapped the dry clutch from a(1953) D8 2U 23,000 oil clutch. The 23,000 D8 #2 rod through a big hole in the block while idling so it was used for parts. Lots of work swapping D8 clutches around but the oil clutch sure operates smoothly.

 

[yblock]

a few more,76v 1974 to1981. 76v00832 after cooler standerd 77voooo1 first pined hard bar 1974 to1981. a situation with cat on strike mid 60s alot of scotish built d8s came to bc.for some reason they wher plaiged with final drive problems and engine problems,droped linners wher 1 isue, they wher soon not imported and no one wanted a used one.customers seemed to forgive us built ks which also had linner isues.machinist in ft vancouver came up with a z sleev which went out to a stronger potion of the block.head gasket blown ter her down and inst 6 zds and no more problems.cat never owned up to the fact a 342 would not live on the west coast.Did you folkes in new zealand have these isues

 

[DPete]

Looks like the same clutch as the 14A and 36A, one hell of a clutch, only weakness is the pump idler gear which is splash lubed and held on the shaft with a wimpy lock ring, keep an eye on it and you're good to go. Oh yeah, if anything leaks it runs right on the stop brake so keep her dry

 

[WabcoMan]

yblock,

We had problems with the liners on the late 270hp D8H 46A's dropping.
One of the reasons I think Cat went with the spacer plate block which seemed to solve the issue.
Final drives were always a problem no matter where the machine was built.
The 235 HP D8H's weren't so bad - perhaps too much HP thru the back end on the later machines.
Still have a very soft spot for those H's & K's though.
Well maintained they are great tools.

 

[Mike Mc]

DP. just take a look at the dry clutch and you'll see why I swapped it out .

Ya it does have a leak around the small top inspection cover that leaks right onto the tranny brake. Only need the brake until the oil is warmed. If I engaging the CCU to raise the blade it quickly stops the tranny. After it's warm and you don't miss a gear it's ok. But the forward reverse lever position is not adjustable so it's tough to change direction on a incline.

Watch the video's agian and see the young operator JR Ponte building a dirt pile as he crunches his abbs to push the lever forward for reverse. The better quality video with a retired Cat skinner uses his foot to throw the lever forward. Love learning from these guys.

http://www.youtube.com/watch?v=sI9yQo4SPyA

http://www.youtube.com/watch?v=6kHHtRUVucw

If you like the video's please give it a thumbs up (if regerstered) so it moves up the ladder of D8 video's. Thanks M-

 

[stinkycat]

But on that old dry clutch with the larger hand hole it sure made changing the the thermond? links (I thank that what they were called last time I changed a set out 50 + years ago) easier

 

[DPete]

Yeah, looks like she might have thrown a few thermoids in her day

 

[Mike Mc]

Here is a link to me starting it. After I engage the pony clutch you can hear the cans fall off the exhaust LoL

Not the best video since the camera is sitting on the fender but if you like it give it a thumbs up so it moves up the ladder. Thanks M-

http://www.youtube.com/watch?v=MHr5E3HQ8BA