CAT 3208 gurus? Q's on governor.

Have an older CAT excavator with 3208. Since the day I got it, it was realized the engine "can" spin more RPM than was intended on that machine. How high? I don't even know because when I got it, I started ramping the throttle with the lever I realized it didn't seem to max out and sounded like too many Rs for it. I put a tach on it and sure enough, I can overspeed it.

Forever, I have been setting max RPM by ear, but I need to put someone else in it and need probably fix this correctly. Any documents and such out there on this? I do have a pile of books on this machine and engine, but I suspect something has been "screwed around" on it. It does seem to apply a governor, or at least boost fuel when needed. The max RPM is just too high. I seem to recall 2200RPM for some reason. That is probably max for the engine, and still too fast for the excavator. I don't need to make change out of the hydro pumps.

That's probably an 1800 rpm unit.. so governor cut off would be..around 1980..
I always set mine to an even 2K.. & bump the fuel 10%..
I hope this helps..

With the machine Serial Number I could probably dig up the FIP and engine speed data. Is it a 235 by any chance.?

A serial number will help
3208 will run a lot faster than you think. 2200 pretty slow for it. I’ve seen them running 2800 to 3000 rpm in trucks.
In an excavator they will be closer to that 2200 mark.

18, 24 & 2600 rpm units are all I'm familiar with..
Applications were> industrial, boats & OTR trucks.. not in any part. order.
There should be a sticker on the valve cover..

Yes, a 3208 can turn 3,000 rpm in factory specs. It probably wasn't set up for that much rpm in a excavator, but the chances of it being the original 3208 in the machine are slim. They aren't hard to speed up, and you can easily slow yours down by adjusting the throttle stroke.

Check your books ,if you have a hyd. testing and adjusting book for your serial # under trouble shooting there will be a section on engine rpm .As I recall there were 2 different engine settings maybe 2100 or 2400 by serial # . In any case use a tach to check rpm not by ear.
Good luck
Bob

8 cyl engines always sound faster than a six at the same rpm- 2 more power strokes every 2 crankshaft revolutions. the 3208 turbo engines run slower than the natural engines ( 2400 in some applications versus 2900-3000 for a natural)

Yes, I mentioned that I have used a tach. Everyone is mentioning how fast the 3208 can spin, and I am over here trying to explain that 'regardless' of what the engine can do, it will spin way higher than the excavator book calls for, which means the pumps are running faster. I will probably turn the Rs up just a bit, but I am asking how the adjustment is made? How does the governor work on these?

crane operator said:

Yes, a 3208 can turn 3,000 rpm in factory specs. It probably wasn't set up for that much rpm in a excavator, but the chances of it being the original 3208 in the machine are slim. They aren't hard to speed up, and you can easily slow yours down by adjusting the throttle stroke.

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Might be worth it to confirm that the injection pump matches the application, is close enough, or is a truck governor. That could explain some things.

These are instructions for turning up a 3208, you're going to want to go the other direction from what these boys are doing. I copied it off the web, rather than type it all out myself. I think the one you are going to want to adjust is the High Idle one, that's toward the rear of the motor, that's to the right in the picture. Called "high rpm governor". You shouldn't have to mess with the one called "fuel rate adj." in the picture. Just the back cover one. These guys are talking about turning one up, you need to slow yours down.

https://www.freewebs.com/nevrenufhp/

"If you look on the top of the injection pump you'll see a cover with 2 bolts. Take it off. Fuel does come out sometimes, and does not need bleeding afterwards. Under it is a screw with a jamb nut. If you hit the accel. linkage you'll see a little pin come up. The screw stops the pin and thus, limits fuel. So adjust it as far up as you can as long as you can tolerate the black smoke. Most turbo'd 3208's can run fine with the screw all the way out(removed). And just behind that is the high rpm governor adjustment. It's labeled as 'high idle', but only go 2-3 turns at a time as to keep it under 3200 no load. Backing the screw out raises the rpm. One more adjustment is the pre-boost power. This is up in the front of the other 2 adjustments. It's round & has 3 bolts holding it & 6 holes in it. Take all 3 bolts out and you may have to smack it with something to break it loose(mosly from paint). Now tighten it like you're screwing it in tighter, that makes the power come in sooner. If you go 'til it stops, then you may see lots of smoke if you mash down on the pedal. Back it out as needed."

Remove>Small 2 bolt cover, Loosen jam nut, Run screw in for LESS RPM. 1/4 turn increments.

Appreciate it guys!
I have no doubt this engine is a different ticker than it was born with. I'd guess the whole engine is probably a truck engine. Non turbo, but it has power to burn in this application. Don't think I ever determined if there were stickers on the engine or not. Stickers would only be a guess anyway because if it was built by Fred in his backyard, who knows whats we gots, but I can say it runs like a top, no blowby, never use Ether, just seems to get the job done. Rest of the machine is a different story....lol

U can adjust the hi speed while the engine IS RUNNING..
I wouldn't use the machines tach.. get a hand- held.. They're cheap on ebay/amazon & useful for all sorts of different applications.

thepumpguysc said:

U can adjust the hi speed while the engine IS RUNNING..
I wouldn't use the machines tach.. get a hand- held.. They're cheap on ebay/amazon & useful for all sorts of different applications.

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Yup, I use an IR handheld tach reading off the crank pulley.