hard cider

I put a cam & lifters in a 237 back in the late 80s early 90s, the 12 lifters where more than the cam. cant remember how much, I was thinking 400 - 500 for the cam, 600 -700 for the lifters

that isn't so bad. IF the truck does not need a whole lot more

I have to wait till I get time to go back and check the truck out more thoroughly.

Fortunately they are not in a hurry to move the thing,

a U, a R, and 3 superliners? you've been holding out on us for pictures....lol

well, they are his trucks with his name on them, so I really should clear it with him before plastering them in the web

Yeah id say a couple hours away atleast. Any pictures of your neighbors U? And yeah U's arent too comon anymore. Im restoring a 75' U685ST.

next time I see him I will ask if he minds me posting a couple of all his

He has a U, with a short dump, An R road tractor, and 3 superliners

I don't see a toggle for the Dynatard or a Jake.

Rob

I am pretty sure it has neither since there is nothing under the valve covers

Tip turbines did have extra parts and weight compared to a chassis mount system but it was a means of cooling the intake charge and cooler air makes more HP. It was the technology of the day and now most things use the chassis mount set up.

With the truck VIN, call around and get the parts prices for the cam,lifters and bearings then you will know. My concern is what else may be a problem after it has been sitting since 2005.

A U686ST was originally a tandem tractor with a single frame. Now. it is has been stretched and added to and at least double frame for use as a log truck. Was this frame work done well or half assed?

Log trucks get lots of abuse so how are the frame rails holding up? Are you wanting to use it as a log truck? You may want to find a DM which would be more suited to being a log truck. Heavier frame, heavier suspension and designed for off road logging service.

Maybe this truck is really cheap. Sadly, I have found really cheap trucks up front are REALLY expensive in the long run.

thanks for all the advice, I will keep it all in mind when I go back for a closer look

I have a neighbor who thinks for sure a lifter face dropped off...

so I really need to check it over well before making a deal, even if it is cheap

tires, batteries, fluid changes etc are probably a sure thing

300-315 HP used water and air in the cooler. 285 HP used just air.

The system used "bleed" air from the turbo to power a small turbine fan in the system to force cool air through the heat exchanger.

sounds like a very unique system, and seems like it would be less efficient. I wonder why the hp rating is higher with it?

thanks for the educating on that

Where is the truck in NY? Im from Northern NY.

hmmmh, rrggh.....ehh. yeah....well I won't be too specific for fear of losing the truck to some crazy U nut.. ..But the truck is in the finger lakes area, Potter to be exact. looks like you are 2 hours or so away?

well, I started this thread to ask about the engine problem. I know it is hard to say anything from a distance. I need to get in there and see what the thing is doing before I start asking you guys. The mechanic had told them it was the cam, and I see a pushrod removed, so maybe it did lose a lifter face. If this is the case, hypothetically, wonder how much a cam and lifters is ballpark?

I will say I am real tickled to see so much interest in this truck, bunch of excited u fans out there

my neighbor drives a u with short dump daily and he was excited too

are these trucks not very common?

anyway, thanks for all the posts guys

Oh boy im a U model nut. Nice U! Where are you from? And the truck is a U686, the 86 in the serial number means it had a 300 from the factory. So you may have the tip turbine missing.

I am from central Va but the truck is in NY

yeah, getting it here may be an issue, the boom is almost 13 feet tall

might have to ......I don't know, haven't thought that far yet

so by the photo above it looks like the tip turbine is a water to air cooler?

why do they call it that?

It has been sitting like this since 2005 with the hood shut though

I don't think any water got in it but if it did it went straight down and can be drained

so you are thinking maybe it has had the intercooler added?

What exactly is the tip turbine?

in the first photo, what is the big pipe in the foreground?

looks like a boost tube to me?

my best guess is that it is air to air intercooled, wonder if the hp is 300?

A friend looked up the vin at the mackshack and it should be the E6 300 2V engine with 5sp and 4.17 rears

ane idea about the miss?

he also mentioned this might be the engine which the faces of the lifters fell off and wiped the cam

also maybe the mack eng brake stuck. can you tell from the pics if it has a brake at all ? I don't see any wires

thanks for all your advice

more

more

ok, got some photos

ok thanks guys, I'll get the pics posted asap. also good to know about the halfcab, never knew there was a difference in the offset vs half

I will be able to tell you as soon as the pictures come, they took a couple from under hood, so I will post them

okay guys,

I have the vin and model

i have picturesas well in a few days

model: U686ST

V.I.N. : 1m2w133y0fa009824

anyone know what I am dealing with for the engine?

any older Mack engine could have a bad cam, could also be worn valve guides. have seen older 237's and 300's sound like they are skipping or the jake is stuck on from excessive Jake brake use and worn valve guides.

I was told by the driver that it was a sudden problem. Ran fine, going down the road, and somewhere on the way back it suddenly started missing

I will get all the other info for ya'll in a few days.

It did say 1984 in the door tag, and i thought I was getting the engine with the 8th

it is a half cab... I can say that for sure, but the rest will have to wait a few days

thanks for the reply

heh heh I will get some and post them since they are so important......why?

The Y is the weight class. You need the letter and 3 numbers prior to the Y.

ok I will get the rest of the VIN

I thought the digits would be the same as regular vehicles where the 8th is the engine code

it will be a few days before I can get them so hopefully you will still reply then. thanks

hello

I am hoping someone can give a little help with a Mack I am looking to buy.

The truck is a 1984 half cab log boom truck with the 8th vin is a Y

first, I need help identifying the engine, what is it?

Second, maybe a little insight on it's problem: the owner said it was driving fine and then started missing and stumbling. Had a mechanic come out who took off the valve covers and told him it was the cam.

Did this engine have a problem with camshafts? Or is there another related issue common?

Thanks in advance for any input