1989 Tucker 1644c

[Blackfoot Tucker]

1BG,

I'm late to this thread...

That fifth wheel plate is "ugly". And being made of T1 steel they should be plenty strong....

I haven't looked lately at the bell housing on my 1986 1544 (360 Industrial with AT545), but from memory it looks different than yours. My recollection of a conversation with Tucker's Jeff Godard is that Tucker had the bell housings made specially for them by a company in Oregon. AT545s were used extensively for many years and behind many different engines, both gas and Diesel. That said, I looked pretty hard and have NEVER found an AT545 (SAE #3 pattern) to a Chrysler LA engine (318 and 360 pattern) adapter housing other than in a Tucker. I wouldn't bet my life on it, but I don't believe Chrysler offered a vehicle with an LA engine and an AT545 transmission as a power train option.

BUT, Chrysler did offer a school bus chassis to bus manufacturers such as Carpenter, Thomas, Wayne and Blue Bird, and it could be spec'd with a 318 and an Allison MT30 transmission. The MT30 is a six speed automatic, but it uses the same SAE #3 bolt pattern.

I also know Tucker has worked closely with the Allison dealer in developing/refining the engine transmission interface. From memory, so I could easily be wrong, that company is Pacific Power Group. I spoke with a very helpful guy there a number of years ago. I THINK his last name was Edwards, and his first name was John, but I could be wrong about that, too. He may be able to help...

Best of luck with the stroker project!

 

[1boringguy]

m1west,

I have I guess you'd say, some personal nostalgic reasons for wanting to work with the 360, so accepting that, I started from there. Also hoped not to much retro fit of to many little things.

My idea for a snocat then, is as much low end torque as can be made with this platform. And a couple of my own druthers thrown in. Going with a 226/230 110° ..050 and .500 lift roller cam, roller lifters, 62cc aluminum heads, 25cc dsh hyp pistons, 1.5 rockers, high volume water pump, and new oil pump. Should be 9.6:1 compression. Using the Edelbrock Pro Flo 4 fuel injection system, which comes as an intake manifold. We'll go through 4-5 cold starts on the dyno building the learning curve for the efi, but I'll let you know how it was setup and what the numbers looked like.

BFT,

If I recall the 318 was an internally balanced engine so the spacer on the end of the crank for the Allison, if the setup is the same,, might be just what I'm looking for, balanced. I'll see if I can chase down anything through Pacific Power Group. Thanks.

I haven't tried to check to see if that's a casting number or part number on the bell housing, but shared it because I thought the little star might be an indication of being from Chysler, or then again it might just indicate it's for a Chysler.

The 5th wheels are at the machine shop getting bushings made. There are a couple of opinions there about fixing the cracks. Let you know how that turns out. My assumption is, that rear 5th wheel cracked like that from weight, although I can't imagine that BC Tel would have hauled more than 2,500 lbs of gear and equipment at a time up to the peak of a mountain, would they

 

[m1west]

m1west,

I have I guess you'd say, some personal nostalgic reasons for wanting to work with the 360, so accepting that, I started from there. Also hoped not to much retro fit of to many little things.

My idea for a snocat then, is as much low end torque as can be made with this platform. And a couple of my own druthers thrown in. Going with a 226/230 110° ..050 and .500 lift roller cam, roller lifters, 62cc aluminum heads, 25cc dsh hyp pistons, 1.5 rockers, high volume water pump, and new oil pump. Should be 9.6:1 compression. Using the Edelbrock Pro Flo 4 fuel injection system, which comes as an intake manifold. We'll go through 4-5 cold starts on the dyno building the learning curve for the efi, but I'll let you know how it was setup and what the numbers looked like.

BFT,

If I recall the 318 was an internally balanced engine so the spacer on the end of the crank for the Allison, if the setup is the same,, might be just what I'm looking for, balanced. I'll see if I can chase down anything through Pacific Power Group. Thanks.

I haven't tried to check to see if that's a casting number or part number on the bell housing, but shared it because I thought the little star might be an indication of being from Chysler, or then again it might just indicate it's for a Chysler.

The 5th wheels are at the machine shop getting bushings made. There are a couple of opinions there about fixing the cracks. Let you know how that turns out. My assumption is, that rear 5th wheel cracked like that from weight, although I can't imagine that BC Tel would have hauled more than 2,500 lbs of gear and equipment at a time up to the peak of a mountain, would they

Thats pretty much the cam in my 73 dodge 4x4 with the magnum. A 408" combo will calm in down some, That cam with 110 lobe centers in my 360" motor is pretty choppy at idol. The EFI should smooth it out some too.

 

[Snowy Rivers]

Good bet BC TEL loaded that critter to the moon and then some.

 

[1boringguy]

Thats pretty much the cam in my 73 dodge 4x4 with the magnum. A 408" combo will calm in down some, That cam with 110 lobe centers in my 360" motor is pretty choppy at idol. The EFI should smooth it out some too.

Seems like the general thought is to go two steps up on the cam for a stroker, from where you would want to be on the stock displacement. That choice was dictated by best low end torque consideration. Hope it's not to choppy or to much of a gas hog.

Too much cam is one of the tough things for efi, reads and adjusts for to much unburned fuel at idle and of course low vacuum. The consensus is that we should ok here. The PF4 requires minimum of 10 inches vacuum and I should have around 17 inches, and of course the extra displacement smooths things out. Hoping I'm happy when I drive it.

 

[1boringguy]

Good bet BC TEL loaded that critter to the moon and then some.

Also wonder about welding induced stress from the bushing installation originally or some other cause, but idk

 

[m1west]

Seems like the general thought is to go two steps up on the cam for a stroker, from where you would want to be on the stock displacement. That choice was dictated by best low end torque consideration. Hope it's not to choppy or to much of a gas hog.

Too much cam is one of the tough things for efi, reads and adjusts for to much unburned fuel at idle and of course low vacuum. The consensus is that we should ok here. The PF4 requires minimum of 10 inches vacuum and I should have around 17 inches, and of course the extra displacement smooths things out. Hoping I'm happy when I drive it.

The 408" small Chrysler is a torque monster, the one I built blew up the planetary gears in a 69 dart with a built 904 shifting from 1st to 2nd @ 6000 rpm. My dodge truck with the 360 magnum is pretty heavy, 1 ton running gear on 35" tires, about 6 mpg city and about 10 mpg on the highway, its fun to drive until you get to the gas station and I am there a lot ( and because of the 10:1 static CR and the cam its premium only ) if I build another truck in my lifetime it will include a turbo diesel.

 

[1boringguy]

The 408" small Chrysler is a torque monster, the one I built blew up the planetary gears in a 69 dart with a built 904 shifting from 1st to 2nd @ 6000 rpm. My dodge truck with the 360 magnum is pretty heavy, 1 ton running gear on 35" tires, about 6 mpg city and about 10 mpg on the highway, its fun to drive until you get to the gas station and I am there a lot ( and because of the 10:1 static CR and the cam its premium only ) if I build another truck in my lifetime it will include a turbo diesel.

Yea diesel definitely has the mileage-power advantage.

And new engine technology is definitely more efficient than the old. Hope the mix here is somewhat efficient, but either way, my snowcat fuel bill is a small expense in the whole picture of this hobby.

 

[1boringguy]

As BFT said, flaws become evident when you sand blast. I think this can just be v'd out and welded ok. Surprises me, the design of this piece seems very stout.

 

[sno-drifter]

The cracking most likely is a result of the operator steering while the cat was not moving. Hence the cracking in the swing frame. And then the fifth wheels. Hard to avoid when stuck up against a tree. There should be a big bold sticker in every Sno-Cat that says DO NOT TURN STREEING WHEEL WHEN NOT MOVING. You might want to reduce the pressure to the steering cylinder. They could have jacked it up.

 

[Blackfoot Tucker]

The cracking most likely is a result of the operator steering while the cat was not moving. Hence the cracking in the swing frame. And then the fifth wheels. Hard to avoid when stuck up against a tree. There should be a big bold sticker in every Sno-Cat that says DO NOT TURN STREEING WHEEL WHEN NOT MOVING. You might want to reduce the pressure to the steering cylinder. They could have jacked it up.

I think Sno-Drifter's analysis is spot on (as per usual).

The first time we took Thundercat out for testing we uncovered a steering issue. At slow speeds we had difficulty turning. I picked Jeff Godard's brain at Tucker, Inc and we modified the hydraulic system to the current production standard of the machine closest in size to Thundercat. (I detailed what we did in post number 32 in the Snowzilla thread.)

The modifications included increasing the hydraulic pump's volumetric output, increasing the output pressure, increasing the flow output from the priority valve and installing a dual cross port relief valve between the orbitrol and the steering cylinder. Increasing the pumps output volume makes the steering quicker, and increasing the pumps output pressure reduces steering effort. The relief valve prevents over pressuring the steering cylinder.

The changes made the steering system work beautifully. But I think they also caused a problem, or made an existing problem worse. My understanding of hydraulic systems, limited as it is, is that the hydraulic reservoir size is sized based upon the system. A larger pump requires a larger tank. Our pump's increased output volume circulates the fluid that much faster, and that generates more heat. The hydraulic fluid in Thundercat was getting way too hot. A significantly larger tank would have helped, but there was no room to modify the existing tank and make it sufficiently larger.

We added the biggest, most capable remote fluid cooler we could find (Derale 15875) and mounted it under the bed. This should remove about 67,000 BTUs of heat per hour. As yet, we haven't tested it in actual use so I can't report on how much it helps. We also plan on using synthetic hydraulic fluid which is more heat tolerant than conventional mineral oil based fluids.

 

[olympicorange]

……. typically the most common cause of heat in a hyd. system , is a restriction, such as a check or relief valve, weak main relief, orifice, hmv/hmu ( steering valve), etc. something new added to the system also. which slows the flow down. the steering cyl. operation & its related components are usually a low heat contributor ( unless the piston seals have leak-by internally), if any at all. so it's the flow from the tank, thru the pump , thru the control valve assy., thru the hmv, and back to the tank, which would be the culprit....

 

[1boringguy]

Thanks sno-drifter and BFT,

That makes a lot of sense explaining the cracks in the 5th wheel and swing frame, and also the seep in the hyd turn cylinder. I'll see what I can do about checking the pressure and flows. Not sure if the quick attach ports at the hyd pump are from Tucker and their checking and setting the hydraulics or from the hydraulics being changed by BCTel. Either way, adding the relief value seems like a good idea.

Given the wear to the ground parts, some replaced grousers, the wear on the hardsurfaced ones, some belts replaced, the sidehilling indications on the boogie wheels, and yet hardly any wear on the engine internal parts, transmission, and differential internals, leads me to do as humans do best and make assumptions.

BC mountains peaks are just pretty much rock. Roads cut to the top, rock. When you need to get to your tower, and your last unloading/turnaround is 5 miles from the tower on the peak and the snow is only the last two miles what are you going to do? You're probably going to take the tool you bought to get there and use it.

I had talked to the gentleman at All Cat Services in Canada when I bought the cat since they had taken them in from BCTel and resold them. He said they took four of these older Tuckers in, and sold them one new cat. They all had low hours showing, he thought probably correct, and they didn't do any work to any of them. People just heard that they had gotten them and came looking for them. Also said BCTel was hard on cats. Perhaps not so much from a desire to be as just the nature of their use. Just a guess but might explain some of what I see with this machine.

Talked to Dan at Tucker in parts, about a couple things today, it was nearly 5 but he was going to see if someone could decipher my hyd pump stamps tomorrow. Or maybe some here knows? Pics below.

 

[Track Addict]

Take a stab at this secret decoder ring: https://www.hydraulic-supply.com/userfiles/ckfiles/files/HydraulicTechInfo.pdf

 

[Blackfoot Tucker]

Take a stab at this secret decoder ring: https://www.hydraulic-supply.com/userfiles/ckfiles/files/HydraulicTechInfo.pdf

That number will tell you the pump's configuration as ordered by Tucker.

But sometimes Tucker modified the pumps as part of the production process. Tucker did not use a single pump configuration for all models, but rather used different pump configurations based upon application. For example, Snowzilla had neither a blade or rear auxiliary hydraulics, and it came with a pump that produced 8 gallons per minute. But that output is based on 1,200 RPM (pump RPM, not engine RPM). I think it's a linear relationship; meaning at 2,400 pump RPM it's producing 16 gallons per minute, and so on.

Your machine and Thundercat both have factory front blades and they had 11 GPM pumps. Thundercat's pump was ordered with a priority valve flow rate of 4 GPM and a pump output pressure of 1,000 PSI. However, Tucker increased the output pressure to 1,600 PSI. One of the modifications Jeff Godard suggested was to increase that to 6 GPM, and when we disassembled the pump... found it had already been done.

I believe your pump was ordered with a priority valve flow rate of 4 GPM, and an output pressure of 2,000 PSI. However, it may have been modified...

 

[1boringguy]

BFT,

You're right, again. Dan (parts) at Tucker talked to Jeff about my pump info, and he said though he couldn't know for sure, he thought Tucker would have drilled my pump out for priority valve flow rate from 4gpm to 8gpm before it was installed. That makes sense if that would be the same amount prioritized to steering as Snowzilla, which has no other real hydraulic demand, and the remainder of the 11gpm pump to other functions.The rest as indicated, 2000psi, ect. Not known however, if BCTel tweaked the pump additionally, without disassemblely or gauges.

 

[1boringguy]

Just a quick couple of thanks in order. First to OO, who said he knew Tucker had these parts a couple years ago stashed in the archives some where and might still be there if someone went hunting for them. Second to Dan at Tucker parts who indeed, did go digging in the Medford attic.

Again could have cut the counter balanced spacer down, but glad to have this one instead. Checked, dimensions and fit are the same, and already balanced.

Also share pics from Dan of other parts related to this that they have in the attic, just as an FYI.

Rebuilding as many of the components as I can before reassembly. Starter and alternator, check.

 

[Track Addict]

Take a look at Drifter's suggestion about changing the wear surfaces and using a clevis pin/set screw on that pivot and upper mount. Just got my parts back and have it all mapped out. Should have pics of the solution next day or two. Details on my 1443 thread.

 

[1boringguy]

Since the photos from the other day seem to be lost in space, I'll try again.

 

[sno-drifter]

Due to the new forum format, I ended up looking at an earlier page and saw your comment about differentials and one being open and a spool in the other. If true, all the more reason for torn up swing frame and lots of other cracked parts. While locked up diffs in deep snow are great, if you use your head, it will raise hell on solid ice surfaces. The tracks do NOT like to slip. Axle fracture is a reality in this condition. Also consider what is going on between front and rear axle with various locker configurations. You do not want one end fighting the other. Open differentials have some real advantages in soft snow when sidehilling.

 

[1boringguy]

sno-drifter,
Of course that makes a lot of sense, especially considering the signs that this cat wasn't always on good snow conditions, and the cracks found. I just assumed that since I'm no expert when it comes to snowcat experience, and assuming that this was the factory set up then it must work. Of course open and spooled diffs would have the same advantages/issues in a snowcat as a jeep, only more so. Had thought about a Detroit locker in the front since the back was spooled, but talked my self out of that. I better stop to see my gear shop this morning as they are about to install the diffs back into the newly powdercoated housings this week. Perhaps e-lockers, if a person is going to go that route, I take it that's what BFT is using, and then some thoughtfulness about use conditions.?

 

[sno-drifter]

Another way to think about it, think of how fast each diff is traveling in a corner. The open diff lets one track go faster than the other= diff going same speed as going straight. A locker which allows the outside track to over speed the inner, wants the diff to travel faster than going straight. Thus different speeds front to back. Tracks say different speeds front to back, frame and connecting parts say no. Hard to argue with physics. Your jeep solves this problem of the front axle travelling a greater distance by tire slip which you feel as that jerking at the steering wheel. With a spool the diff is trying to figure out which track it wants to agree with. A four track Tucker wants both diffs travelling at the same speed.

 

[Blackfoot Tucker]

1BG,

We did install E-Lockers in both Snowzilla and Thundercat. I think selectable lockers are the best option, and then your choices become either ARB air lockers or Eaton E-Lockers.

My recollection is the ARB Dana 60 locker has always been a four pinion design. The first generation Dana 60 E-Lockers were two pinion, but they changed to a stronger four pinion design and surprising no one, jacked up the price substantially. They’re not cheap and I saved a fair bit by reaching out to several vendors looking for a better price as I was buying four. Unfortunately, neither machine is operational, so I can’t comment on how well they work.

A few years ago I had the opportunity to demo a new Tucker 2000XL equipped with E-Lockers. Tucker has theirs set up so you control the locking function of both differentials with a single switch. We wired ours with two switches, so the front and rear are controlled independently, but I honestly don’t know if there’s any benefit to that.

I think you’re discovering one can sink a lot of moolah into a snowcat…ask me how I know! To paraphrase the late Senator Everett Dirksen: “A few thousand here, a few thousand there, pretty soon, you’re talking real money”.

 

[1boringguy]

sno-drifter,
I hadn't thought it through quite that far. I figure I'm going to have to buy parts to convert the spooled diff to open, so might as well spend a couple extra bucks and buy the e-locker. But as you point out having only one end locked is about worse case scenario. A jeep has off track which a 4 track Tucker doesn't, so eliminating some difference between front and rear there. On paper I guess,, with the front and rear locked and both carving the same arch, diff speed should be the same, no? Perhaps one reason Tucker puts front and rear on one switch. Thinking also in deep snow it's not such a big deal, but otherwise Terra Tracks probably allow for a little easier slippage to compensate than belted tracks with steel grousers. Again, some thought is prerequisite about use of lockers in various conditions if not going straight up a hill. And I suppose most of the time one would want them is in deep snow, well if you're not dragging a groomer anyway.

BFT,
I'm thinking if I go with lockers it will be the e-lockers, but my gear shop is checking on those for the dana 70. So the choice seems to be do both front and rear or neither. The question then is how much would i need/use the locking? The trouble is I don't have much experience, and I haven't had the 1644 and the Patrol out at the same time, but I wonder if the Patrol will just end up being better in deep snow anyway. Just because it has about 17% more track on the snow, infinitely variable drive to all of that track, and grousers that have twice the bite depth of the 1644. Idk, I'll have to chew on it, but not hard to add the lockers later either. It's just money you know. ?

Thank you both for sharing your experience with me, as always.

 

[The Sweet Wbj1]

Just to prequalify my comment beforehand.... I am from Georgia. We get zero snow and I don't even own a snow cat so take it for what it's worth.

When I borrowed TLBFT's 1544 for our Christmas trip one of the things I was excited about was the sledding hill by our cabin. It's actaully a logging road that goes up to some big cliffs that supposedly turn into "ice cliffs" in the winter. I was excited to pack the sledding hill for the kids and maybe go see these ice cliffs I had heard about. That never panned out. The sledding hill is not all THAT steep, but is long. The 1544 just would not make it even to the very top of the sledding hill. It would start to spin one front and one rear track every attempt. I did not push it because apparently you aren't supposed to spin the tracks and I was not going to be hard on a machine I had borrowed. I backed up a few times and tried to get some speed up, but ended again with tracks spinning. Maybe it's because we get sugar snow at the cabin, I don't know. There was about 4' of snow on the ground. It was kind of disappointing for all the "no hill too steep, no snow too deep". At that moment I was VERY thankful I had spent the money on lockers for Snowzilla and I am sure there will be more in the future. Here's a video just for reference of the hill. The 1544 would NOT go any higher than where all the kids are sitting at the very start of the video.

 

[Track Addict]

Another idea to fix the traction problems would be to install 500 series pontoons and tracks and forgo locked differentials.

Just sayin....

 

[1boringguy]

WBJ1,
Not the expert here either but listening and thinking. Jeep'n vs Snowcatting might not be quite as drastic of a mentality/experience shift as say driving to flying, but along the same line I think. Lots of factors play into what one thinks is climbable at a given moment; machine, snow conditions, oneupmanship (particularly if there's someone around to hold your beer), ect. Watching some videos of personal cats playing in the snow gives a glimpse of what realistic expectations look like I think. The second video is of, I believe, ff participant wakeup call's 1642. If you watch it closely you can see the rear tracks stop intermittently, indicating open diff functioning. I'm wondering if any of the Colorado guys have lockers on their Tuckers who might share experience?

And what does a go anywhere (or as close as it gets) cat look like? Probably something like this ?

For me, I'm thinking of it like the jeep I guess. I'm not a rock crawler so I don't use them much, but when I do need them it's damn nice to have them. ?
And confidence factor in your equipment when you're 15 miles from the truck counts for something.

 

[1boringguy]

Another idea to fix the traction problems would be to install 500 series pontoons and tracks and forgo locked differentials.

Just sayin....

Hmm, just curious if anyone here has ever done that conversion?

 

[Track Addict]

I think more have gone pontoon to rubber track but I bet that a person with a severe disdain for rubber tracks has converted a nice rubber body back?

 

[The Sweet Wbj1]

I've heard the pontoons have better floatation and rotate MUCH easier that the belted tracks. I am just not down for all the extra maintenance and lack/expense of all the rollers.