Who makes the TAD and SW Diesel Serpintine pulleys?

[evm1024]

I've been thinking about a serpentine pulley kit for my Perkins 4.236 and noticed that the kits from various vendors look much the same. So the question is:

Who makes the pulleys for them?

TAD, SW Diesel, Balmar (altmount)

[evm1024]

I ended up ordering the pulleys from SW Diesel and will need to make a few things. I'm thinking to report on progress in this thread instead of making a new one....

The pulleys are ordered individually from SW Diesel and came in about a week. TAD and others have full kits. I've not called Balmar but they do not list a 4.236 in their product list.

It is interesting to note that the water pump pulley has a vee bely groove in it so that should need to you can revert to using the vee for your alt or another use.

The crankshaft pulley mounts on the front of the crank pulley and thus has the original vee groove available.

The serpentine belt will be forward about 3/4" so the alternator will need to be mounted that much further forward. The spacer to do this is included in the TAD kit. I'll just have to make my own.

Also, rather than reuse my existing coolant pump I've ordered a replacement. The old can be a spare.


Here are the pulleys:

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Here they are on edge.

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The first step is to mount the new pulley on the front of the existing crankshaft pulley. First I needed to clean out the 4 holes in the existing pulley. They had 30 years of gunk built up in them.

I started with some deoxit-5 on a 1/2" round wire brush. This cleaned out a lot of the junk from the holes.

Then I used a tap to clean the threads. After wire brushing the tap went in nicely.

Lastly I will de-grease the threads so that the thread locker will be able to do its job.

The frount surface of the existing pulley has been sanded to remove surface rust and present a flat mounting surface to the new pulley. The insides of the new pulley will be coated with tef-gel and then bolted in place.

This photo shows the serpentine pulley mounted to the existing pulley. This is a test fit before using thread locker to be sure that there are no problems (like the pulley wobbles).

The bolts are grade 8 - 7/16" x 1.25" 20 tpi and I'm sure that they are overkill for the application.

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THe new water pump arrived. I did some dry mounting of the pulley. It is a tight fit so I did not push it on very far. It will ge a coat of tef-gel on the shaft and then the nut will pull the pulley onto the shaft. Lastly, I'll torque the nut.

[evm1024]

Well, I got a little more time to work on the serpentine conversion for my boat.

I bought the pulleys from SW Diesel for a good price. The kit from TAD has the same pulleys but costs more by a bit. However, the TAD kit comes with the alternator spacer that is required to move the alternator 3/4" forward.

Being a DIY kind of guy (as are so many sailors) I decided to make one myself. TAD would want $90 for the spacer if they had any to sell.

The Alternator needs to move 3/4" forward because that is the thickness of the vee-belt pulley that the serpentine pulley mounts on.

The first step was to remove the alternator and alternator bracket. That done I sent the alternator off to PMX here in Portland for an inspection and rebuild. I also have a 150 amp Helr alt that is really dirty so I sent that off to PMX as well. Bill is a great guy and knows his stuff and gives super service.

In addition to new brushes, bearings, checking diodes etc I had PMX install the 6 groove serpentine pulleys. PMX charges $100 plus parts and considers the alt to be remanufactured.

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It was time to get busy making the spacer. Based on info from the web including the photo of TAD's kit from their website I decided that the space could be made from a 3" long piece of 2" wide, 3/4" thick mild steel (a36) bar stock.

I went over to our local Metals Supermarket and for $5 they cut me a 3" piece of 2" x 3/4" bar.

A36 machines well and is easy to work with. The forces are low and mostly compressive so it is a great choice. But any mild steel would work.

Here is a rough drawing of what needs to be made....

I have indicated that the mounting bolt is hex head but this is allen head. The white section is the spacer I needed to build.

The shaded section is the existing alternator mount, and the offset between the bolt that mounts the alternator bracket and allen bolt that mounts the spacer plate is 3/4".

I used a Q drill for the pilot holes then a 3/8"-24 tap for the bracket mount.

The allen head bolts need to align with the existing mounting holes on the engine block. So rather than use a 3/8" drill for those holes I used a larger drill ( 13/32" ) to give some tolerance for alignment.

But before starting that hole I drilled the recess for the allen head cap bolt using a 1/2" pilot point drill to make the pocket for the allen head bolt.

The pilot point drill starts with a small set of cutting faces and outside of those are flat cutting faces to the full width of the drill. Sadly the allen head diameter is more then 1/2" so I ended up in enlarging the pocket with a 5/8" tungsten carbide concrete drill I had laying around.

It would have been better to use a larger pilot point drill but I had the 1/2" already and the cost of the concrete drill (about $8) was less than the cost of a 5/8" pilot point ($25).

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I don't have a milling machine in the garage anymore so this was all done on a drill press. It could have been done with an electric hand drill motor and a vise.

Here is the final results assembled.

Of course it needs to be painted....

I did take the time to trim the spacer on the alt bolt so that I could get a few more washers in. With the washers the alt could move forward and back a bit and I would rather have it mot moving around or need to tighten the bolt so much that the mounting bracket is bent a lot.

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Here are some closer looks at the spacer plate....

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Lastly, the allen head bolts are "captured" inside the spacer plate.

The installation requires that the existing mounting studs be removed from the engine block and the spacer plate bolted (using the allen heads) in place.

The thing to look for here is that these mounting holes are through drilled and if the allen bolts are too long they will make contact with gears inside the engine. This would be very bad for your engine. (camshaft gear I think)

The studs only screw into the block about 1/3" and thus you should get allen head bolts that are only long enough to go 1/3" into the block.

When mounting them use loctite after cleaning the threads.

I will be measuring the depth when I get to the boat to install this bracket but will keep to the 1/3" depth unless I see that there is a lot more space.

Here is a side view of the allen bolt in place in the spacer.

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One last update re the mounting bolt depth.

On my 4.236 I can screw the bolt into the block 18 turns till it touches something (gear teeth or???) That works out to 3/4" (18/24).

On the spacer plate I made the allen head bolt screws in 8 turns or about 1/3" (8/24). Leaving more than 3/8" clearance. Sounds like plenty.

Everything mounts up nicely and in alignment. The tension arm need to be straightened so as to make sure it did not hit the expansion tank.

[evm1024]

Well now I got a bit more time on the boat this weekend. The short of it is that the serpentine kit is installed and working. No photos yet, it was messy and I did not want the camera anywhere close to it.

There was of course some drama....

I started out taking off the water pump to put the new one on. I had put the serpentine pulley on the new pump a while ago. I just wanted to install a new pump and use the old as a spare.

After draining the coolant to a lower level I pulled the header tank off. This exposed the thermostat. This engine takes a 63mm dia thermostat (about 2.5") which my local auto parts store had in stock. More on that later.

Going after the water pump 3 of the 4 mounting bolts came off with a normal amount of force. But the last one just would not budge. Ranter than use BFI (Brute Force and Ignorance) I took this as an opportunity to buy an electric impact wrench.

That bolt came off without any problems. I can use the impact wrench other places. I've been needing one for years. It set we back $133 at Lowe's. Money well spent vs a mangled mess.

The pump is actually 2 pieces - the actual pump and a pump housing that bolts to the block. The pump housing is reused and the pump bolts into it. (gotta be a better name than pump housing which is really is not).

With the new pump installed into the housing I bolted it back onto the engine. Now I had all 3 serpentine pulleys installed and was able to measure the size of the belt needed. Off to my local NAPA and I had a K06052 (52") Gates green stripe 6 groove belt in hand.

That took up the day and it was time to head home to make pasta.

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Starting again today I installed the belt and spacers for the tension arm. The tension arm needed to be straightened a bit so that the alternator would move from one end to the other without hitting the header tank on one side or the alternator on the other. I just put it in a vice and flattened it out a bit.

The old pump had the port open for a heater, the other end of the circuit is on the head. But there was no heater core so the PO just ran 6' of heater hose. The new pump has a plug in the port so I decided to pull the host and close off the port on the head.

The port on the head had a Tee and that is also where the temp sender is. Just a bunch of brass fittings... Should be easy right?

Of course all but the fitting in the head came off easily. The one in the head was a 3/8" NPT nipple - or should have been. The nipple was threads from one end to the other and of course was frozen into the head.

I worked on it with vice grips and heat and PB Blaster and then a chisel. Nothing, not a budge. Expecting the worst I dug around and found a 3/8" npt tap and get a 9/16" drill. 37/64" is the normal hole size for a 3/8" npt tap but 9/16" (36/64") is listed as an alternate. I figured that 9/16" would be safer and less likely to damage the threads.

Using a cordless drill (and a shop vac) I drilled into the brass nipple. I had already cut the brass off flush with the head and at low speed drilled through the nipple

Now luck would look my way. As I poked a bit of brass off the edge I was able to grab it with some pliers and pull it out of the threads all the way to the bottom. Using the 9/16" paid off. Kinda like opening a can of sardines the brass just unwound out of the threads. No need to tap the head. the threads were undamaged.

I bought a brass coupler (3/6" male, 1/2" female) and screwed that into the head. The temp sender was then screwed in the the coupler. Great, now we do not have 6' of hose waiting to go bad and the them sender was installed.

The thermostat was installed, I cut a new gasket and installed the header tank. Tension the alternator, with up the harness and positive and negative cables to the house bank. Fill the header tank with coolant and we were ready for the moment of truth.

Turning the key the engine starts normally, No bad sounds - is good. Water pulses out the exhaust and everything looks normal.

The alternator is only a 100 amp unit and at 1000 rpm (need to recalibrate due to the 1:3 pulley ratio) the alter is putting out 40 amps or so. Then up at 1800 rpm the alt is running at 80 amps into a 90% SOC 700 LiFePO4 bank. Bulk is set at 13.9 volts (I'll change this to 14.0 later)

Up at 2000+ RPM I'm seeing 100 amps or so. Not bad.

[evm1024]

The temp kept climbing. This is normal for this engine and for many 4.236. Their thermostats do not have a jiggle valve or air bleed hole and at least in my engine the temp goes up to around 210 then drops rapidly to 185 when the thermostat opens.

Nothing like that this time. It just went up and stayed up.

I'm guessing I have a pretty big air pocket in the coolant system.

Out of time so the engine is shut down before it gets too hot.

Next time I'm there I'll pull the header tank and drill a 1/16" air bleed hole in the thermostat and see if I can do a better job of filling with coolant.

It also appears that there is a slight leak around the temp sender. I could torque it down more to see if that stops the leak or I could put a different set of fittings that give more depth of threads for the sender.

Time will tell.

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Oh Yes, one more thought.

I think I'll (once the temp issue it fixed) switch over the the HEHR 23-12M 150 amp alternator I had rebuilt at the same time as the 100 amp Balmar. The Balmar has better overall low speed output but the Hehr Powerline may provide more current at 1000 rpm idle (3000 rpm on alt) and 10 or 20 amps more at WOT (2200 engine RPM 6600 alt RPM).

In any case I plan on an AT-160 later. It will be interesting to see the differences in output between the 2 alternators.