Chrysler IND 33 rebuild

[Loren]

I finally got the cam back!

Some back ground: an IND 33 is basically a forklift engine. It has a gear driven cam instead of a chain driven cam. The reason is to drive the hydraulic pump for the forklift equipment off the top of the cam gear. I had a WWll vintage Clark Carloader that had a Continental engine that was the same configuration.

One of the nice things about gear driven cams is that there is no chain to get sloppy.

There are some costs however. The cam rotates backwards so you need an oil pump with a different gear. The fuel pump eccentric is at the rear of the cam (because of the position of the hydraulic pump) so you either use the IND 33 block or go with an electric pump.

If you ever wondered why the oil pump has two ports then a cross over tube to the other side of the block this is why. If the cam turns backwards then the oil pump does too. So the inlet becomes the outlet and so on. All they had to do is screw in the tube to the right port.

The cam gear is a shrink fit in stead of a bolt on. So you chill the cam and heat the gear and in theory they should press together easy. That technology kept my cam from being ground for months...til I asked for it back.

Here's some photos to show what I am talking about.

[Frank Elder]

I love learning on this forum thank you Loren..... too bad you can't fit a third cog in there somehow then you wouldn't it wouldn't have all that backwards nonsense.

[Merle Coggins]

Interesting that Chrysler used that technology on the industrial engines. I've worked with many diesel engines with gear driven cams. It's fairly normal technology in that world. In some engines they are geared directly as you show, and in others there are idler gears between the crank and cam gears. On the newer Volvo engines, with overhead cams, they are still gear driven with several idlers in between. Some of these idlers also drive other accessories. Obviously cams can work in either direction as long as they are ground properly for that rotation direction. 

 

Was the delay in getting your cam ground due to the lack of understanding of the reverse rotation, or just because you weren't important enough for them to get on it? We would all hope that all customers would be treated with equal importance, but in reality the high volume customers tend to get more attention. 

[Loren]

The delay was because they were worried about messing things up. There was much handwringing but no action.

Since you brought it up I suppose I should tell you how I got the gear off.

I put the cam in my press and applied just a little pressure, then applied plenty of heat from an acetylene torch.

Once it was good and hot I applied more pressure and it came right off very easily.

To put it back together I left the cam in my freezer overnight. I set up the press with a bearing separator fitted to the number 1 cam bearing and heated the gear. When it was good and hot I fitted it over the snout of the cam and it went half way on. The I pressed it the rest of the way with minimal effort.

 

To tell what rotation cam you have remember the 4 strokes of the engine. Exhaust always leads Intake.

Auto engines run clockwise looking at the front of the car.

Even a VW turns clockwise when you open the engine cover to look at the engine. (That's why Subaru engines are swapped into Vanagons).

A chain driven cam turns the same as the crankshaft and a gear driven cam turns counterclockwise.

So looking at the cam front the gear/sprocket end you will see the direction of rotation by the exhaust lobe.

There are some engines that have gear or chain drive such as Ford V6 which was made both ways (the later versions were chain).

 

To grind a gear driven cam with a chain drive master, you just turn the master around in the machine.

In the photos you will see the stainless steel wire used to hold the thrust plate in place.

Edited October 16, 2020 by Loren

[Merle Coggins]

We often heat gears or bearings in oil to ease press fits onto shafts. I've also frozen shafts or bearings in dry ice to shrink them to ease pressing. I've also done both as you have. Usually if it doesn't slip together quickly, before the heat starts to transfer, you're screwed and will need a good press. The key is to have everything setup and ready, then work quickly. 

[James_Douglas]

I wonder if my IND-265 engine has a chain or is direct...I have pulled the head and it looks like there is almost no ridge in the top of the bore. It is STD. But, after your post, I wonder about the cam and gears...

 

James

[Loren]

This is one of those "Did you know?" posts.

The oil cross over tube from the oil pump to the galley is a 7/16" tube.

Did you know this is a size nobody makes fittings for?

Of course when the engineers worked on the flathead 6 engines that was not even a consideration. The Dodge Brothers machine shop built parts for a lot of car manufacturers and delivered complete running chassis to Ford until 1914. They could (and did) build just about anything the designers wanted and did even special parts like they were everyday.

 

The engine I am working on was a bare short block. The oil pump, cross over tube and some other things simply weren't there. I could buy a surprising amount  of this stuff NOS. Vintage Power Wagons supplied the NOS Oil Pan, NOS Pick Up Tube and used Pick Up Screen assembly. 

A Cross Over Tube had to be made. 3/8" and 1/2" fittings are commonly available. 1/2" won't fit inside the pan so 3/8" it is.

Because the 3/8 tube is smaller than the 7/16, I wanted to make sure the bends were perfect large radius with no kinks or flat places to restrict the flow.

Steel tube from the hydraulic shop was used because it has a nice heavy wall and no seam.

You can bend a tube perfectly by filling it with a low temperature melting metal such as "Cerro Bend Alloy" which is a brand name for "Woods Metal".

Woods metal is made of Bismuth, Lead, Tin and Cadmium which melts at 158 f degrees. Because of the Lead and Cadmium it is considered toxic however unless you work with it all day every day your exposure level is minimal.

 

I heated up a mini Pepsi can with a propane touch and poured it into the 3/8 tube, then let it cool. As Cerro Bend cools it expands and makes a tight fit to the tube. When it was room temperature I proceeded with my bender. Since you are now bending a rod as apposed to a tube it's not easy. You should lube the bender and have a vice handy. Once bent and trimmed I put the work piece in a pan of water and brought it to a boil. The Cerro Bend was coming out in little metal balls before the water boiled. A few taps to make sure it was all out and it was ready to put the final double flare on the tube.

 

It was easy to do and solved the problem I had with the reverse turning oil pump.

Here's some photos.

[TodFitch]

Nice work!

[Dodgeb4ya]

On 10/17/2020 at 4:02 PM, James_Douglas said:

I wonder if my IND-265 engine has a chain or is direct...I have pulled the head and it looks like there is almost no ridge in the top of the bore. It is STD. But, after your post, I wonder about the cam and gears...

 

James

Pull the front tappet cover and look towards the front chain/gear area...see what you have.

[Tooljunkie]

Fascinating! 
just did a little reading on the cerrobend. Interesting stuff.  
3/16” and 1/4” tubing isnt hard to work with, but this cerrobend makes for a nice finished product as you have shown. Especially with the heavier wall hydraulic tubing. 

[Sniper]

Very nice work and very helpful information too.

[Loren]

The quickest easiest way to tell from the outside if an engine has a gear drive cam or a chain drive cam is which direction the distributor turns.

In fact all you need to do is find plug wire #1 and then the next cylinder in the firing order.

Which side of #1 its on will tell you the direction the distributor turns without getting your hands dirty.

I'd look it up right now but I'd might wake up the dog and that would not be good.

 

[Andydodge]

Nice work and we've all learnt something..............thanks..........andyd