Using HEI modules for other types of distributors

One of the upgrades initially slated for the Scout was the ignition system. One of the options I considered was modifying the system to use and HEI Module.

Many Scouts originally came with the dreaded ‘Gold Box’ ignition module. Scout owners can tell you, this item is often problematic. As a GM fan from way back I have wanted to add an HEI to my 345, but alas, the factory dizzy with the Hall Effect trigger won’t work with an HEI module. Since the IH engines are a bit old there are a limited number of aftermarket parts built for it. There are some instructions out there for modifying the stock distributor with Ford Duraspark parts, or there are some companies that build custom HEI distributors.

Just for reference, here’s a link to a wiring diagram for attaching an HEI module to other types of distributors.

Replacing an HEI distributor in a 300 Buick V8

This is the first non-IH related post on Bob’s Bad Binder.

Basically this article was on another site, and all automotive items will be moved here. These will probably be rare.

My everyday driver is a 1965 Buick LeSabre with a 300 V8. This is a great engine – I can get over 20 mpg on the highway. One of the modifications I made was to replace the point type distributor with a GM HEI out of a later model Buick 350 V8. The distributor fits correctly, but did require some slight modifications (grinding) to the intake manifold. The power, performance and starting after this modification has been tremendous. I would suggest puting an HEI in any vintage GM product if there is a direct replacement.

Project: TBI Fuel Injection – Fixed

Back in the spring of this year I purchased a fuel injection kit for my Scout II from Affordable Fuel Injection (For those of you interested in the kit, it looks like it’s now only available through IH Only North).

Jason and I installed the kit this summer, but the truck never ran right. It always seemed to run too rich. Our first thought was a low vacuum signal due to the somewhat large cam I have in my 345. I contacted AFI support, and they told us it had to be a vacuum leak – the cam shouldn’t cause the problems we were seeing. We worked to find a vacuum leak, and finally determined the EGR valve was bad. We blocked off the EGR and improved the vacuum, but the GM TBI system still didn’t seem to work correctly.

The summer went on and we got busy replacing the floors. The fuel injection system took a back seat.

Finally, this weekend we decided to see if we could get it fixed. We installed the O2 sensor, which shouldn’t have been a major factor. The O2 sensor only works when the system is in the feedback loop. An engine will generally run without an O2 sensor, it just runs better when the sensor is working correctly. Again, the O2 sensor seemed to help, but things still weren’t correct.

The next step was to run through the AFI troubleshooting steps. One of the steps is to check the fuel pressure. The GM TBI system does not include a schrader valve to connect a fuel pressure guage to, and when we initially installed it an adapter to add an inline valve for testing. Since then Jason had acquired the needed adapter, and yesterday we were able to test the fuel pressure. After attaching the adapter to the pressure side of the TBI, we started the engine. Fuel pressure was measured at 40 psi. Correct pressure for the TBI system is 12 psi. Immediately we knew we were on to the problem.

Jason thought the TBI internal regulator should be control the pressure, and thought maybe the regulator was bad. The next step in the troubleshooting guide was to test the return side of the fuel system. We reconnected the adapter to the return line and started the engine again. The pressure? Again… 40 psi. Obviously this was a problem. We had some kind of blockage on the return side of the system.

Next step was to check the return line. I proposed we take the hose off between our new steel fuel line and the tank and run it into a gas can. This done, we started the engine – and found it ran MUCH better.

The troubleshooting guide continued with a recommendation to verify that the correct port was used on the fuel tank for the return line. A vent line may contain an orifice that would restrict return flow and cause a backpressure problem.

33 Gallon Scout II Fuel Tank
My Scout II has a 33 Gallon aftermarket fuel tank, like this one from scoutparts.com. This was a donation from my Dad’s project Scout II – Al. It was installed when we bought Al and he let me have it for mine. The tank is a great improvement over the 19 gallon stock tank, but is a bit of a nightmare to install. It’s designed to fit between the frame rails with only enough wiggle room to get the filler neck past the frame. At this point, we were sure we would have to pull the tank – not a fun job. We raised the Scout up and I examined the fuel line attached to the tank looking for a problem. Immediately I realized the problem was very simple. When we had installed the tank, the return hose had been kinked between the frame and the tank. I gave the hose a yank, pulled it out from where it was stuck, re-attached it to our steel line. Presto, problem solved.

My TBI fuel injection system now works as promised. For the first time since we built the 345 for my Scout actually seems to have a will to live. No more problematic carburetor, no more Gold Box ignition, hopefully no more engine related problems.

At this point, the only remaining fuel injection issues are mounting the ECM and checking the return line to make sure to flows to the bottom of the tank. Still have some floor work to do, and need to mount the seats, but then we can actually do some wheeling!

Project: Scout Floor Replacement

Bob’s Bad Binder has been on the sidelines for a while due (paritally) to bad floorboards. The rust was so bad that the seat was barely mounted and the seat belts had pulled right out of the floor.

In early July we started replacing the floors.

Jason has replaced floors and rockers in several Scouts, and this one was the worst he has seen to date. Typically the floor only has to be cut out to the support, but we had to cut the driver’s side all the way to the hump.

This project is still in progress, hopefully it will be completed soon.