90' international 3700 build

MengerMayhem · 01-28-2018, 07:38 PM

I have a 1990 International 3700 with the 7.3L idi and an automatic transmission with out an overdrive. We go the bus for free from a friend that just wanted it off his land. As of today, Ive driven it home, taken all the seats out, pulled up the floor and wire-wheeled the rusted spots. Nothing has been hard just tedious and seats where a 2 person job for sure.

Long term plan is an RV conversion for my Wife and 2 boys and I to adventure in.
Im a mechanic and novice fabricator so I plan to do all the work myself. Im not familiar with the drivetrain but have been reading up on what upgrades are available for the motor.
I dont know what trans in on it or where to find it. also the motor desegnation or model. all i know is that its the 7.3L idi none turbo.

I want to do solar panels and a deck on top.
I can get an ambulance generator for 1k$ but have no idea where to start with what my electrical needs are/will be or what all ill need to install the system. I do have basic electrical knowledge.

I plan to rebuild the motor with new gaskets/lines, and while I'm in there check on the condition of the internals. I also want to add a turbo to it, knowing i might need to do something about the high compression pistons if i do so. Any thoughts and suggestions are welcome.

Next step is removing wall and roof skins and start looking into spray foam insulation.

jjhwick119 · 01-28-2018, 07:52 PM

Good looking bus! i bet your heads full of ideas seeing that nice empty floor in there.

I believe there should be a plate on the side of the trans that will tell you what it is, and maybe on the motor too. if not on the motor, go to https://www.gates.com/search-by-vin with your vin number and itll give you some info about it, including motor. there are other online decoders, but ive found gates usually has more info than others

MengerMayhem · 01-28-2018, 07:57 PM

fantastic, thank you

Jdawgsfanasty · 01-28-2018, 07:59 PM

Quote:

Originally Posted by MengerMayhem

I have a 1990 International 3700 with the 7.3L idi and an automatic transmission with out an overdrive. We go the bus for free from a friend that just wanted it off his land. As of today, Ive driven it home, taken all the seats out, pulled up the floor and wire-wheeled the rusted spots. Nothing has been hard just tedious and seats where a 2 person job for sure.

Long term plan is an RV conversion for my Wife and 2 boys and I to adventure in.
Im a mechanic and novice fabricator so I plan to do all the work myself. Im not familiar with the drivetrain but have been reading up on what upgrades are available for the motor.
I dont know what trans in on it or where to find it. also the motor desegnation or model. all i know is that its the 7.3L idi none turbo.

I want to do solar panels and a deck on top.
I can get an ambulance generator for 1k$ but have no idea where to start with what my electrical needs are/will be or what all ill need to install the system. I do have basic electrical knowledge.

I plan to rebuild the motor with new gaskets/lines, and while I'm in there check on the condition of the internals. I also want to add a turbo to it, knowing i might need to do something about the high compression pistons if i do so. Any thoughts and suggestions are welcome.

Next step is removing wall and roof skins and start looking into spray foam insulation.

Can't beat the price! Your 7.3 is a cousin to the power stroke so you probably know more than you think...the tranny is probably a Allison...run your VIN though the Gates VIN finder...you'll get you specs there...welcome to skoolieville!!!

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Tango · 01-28-2018, 08:04 PM

Allisons typically have the plate on the passenger side of the trans. They look like this (but usually under a lot of grease & grime).

MengerMayhem · 01-28-2018, 08:31 PM

Manufacturer International/Navistar
Make International
Model Year 1990
Model 3700
Engine Manufacturer International/Navistar
Engine Series T444
Engine Capacity V8, 7.3L (447 CID)
Fuel Type Diesel
Vehicle Type City Transit Bus
Chassis 4x2 FBC Bus Chassis
Drive Line Type 4x2
Brake System Air
GVWR Class 26,001 - 33,000lbs.
Country US Produced Incomplete Bus
Assy. Plant Springfield, Ohio

Ill have to get trans info when i get off shift, thanks for the info people!

Mr4btTahoe · 01-28-2018, 11:01 PM

The ol' IDI and the powerstroke are completely different animals.

Up until recently, there was very little support for IDI performance parts but that has changed. Check out R&D IDI Performance - Home The owner's name is Justin Anderson... he is basically a 1 man show and puts out top notch parts.

Now.. as far as what can be done to them. How many miles are on the engine? Very well might not need a rebuild. Rebuilding these engines gets pricey quickly as parts are getting harder to come by. Nearly every rebuilder suggests sleeving all 8 holes as these engines are prone to cavitation (pinholing the cylinderwalls) when the correct coolant additive isn't used or monitored.

If mileage is low... say under 200k and it doesn't knock or have a LOT of blow by.. I would say just pull the heads and have them gone through by a shop that knows the IDI. Valve guide wear is a common issue so make certain they replace all the guides. Put in some head studs and fresh gaskets. Replace injectors and the injection pump (R&D builds some nice pumps and injectors) and a turbo kit (R&D also builds some really nice turbo kits but they aren't cheap. You can find the old banks and ATS 093 kits used from time to time for around $600-800).

These engines were never designed to be a power house... but they were designed to be work horses... built to be ran on the governor at full power.. day in and day out without fail. They also really like alternative fuels. I currently feed 3 IDIs on processed waste motor oil.

How does the bus feel currently as far as power goes? Will it run highway speeds? How much faster does it need to be for you to be content? This will help decide the route to take as far as power adders go.

Looking forward to your build!

Jdawgsfanasty · 01-28-2018, 11:24 PM

Quote:

Originally Posted by Mr4btTahoe

The ol' IDI and the powerstroke are completely different animals.

Up until recently, there was very little support for IDI performance parts but that has changed. Check out R&D IDI Performance - Home The owner's name is Justin Anderson... he is basically a 1 man show and puts out top notch parts.

Now.. as far as what can be done to them. How many miles are on the engine? Very well might not need a rebuild. Rebuilding these engines gets pricey quickly as parts are getting harder to come by. Nearly every rebuilder suggests sleeving all 8 holes as these engines are prone to cavitation (pinholing the cylinderwalls) when the correct coolant additive isn't used or monitored.

If mileage is low... say under 200k and it doesn't knock or have a LOT of blow by.. I would say just pull the heads and have them gone through by a shop that knows the IDI. Valve guide wear is a common issue so make certain they replace all the guides. Put in some head studs and fresh gaskets. Replace injectors and the injection pump (R&D builds some nice pumps and injectors) and a turbo kit (R&D also builds some really nice turbo kits but they aren't cheap. You can find the old banks and ATS 093 kits used from time to time for around $600-800).

These engines were never designed to be a power house... but they were designed to be work horses... built to be ran on the governor at full power.. day in and day out without fail. They also really like alternative fuels. I currently feed 3 IDIs on processed waste motor oil.

How does the bus feel currently as far as power goes? Will it run highway speeds? How much faster does it need to be for you to be content? This will help decide the route to take as far as power adders go.

Looking forward to your build!

Sorry...I am either misinformed or I misunderstand...

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Mr4btTahoe · 01-28-2018, 11:32 PM

Quote:

Originally Posted by Jdawgsfanasty

Sorry...I am either misinformed or I misunderstand...

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The only thing the powerstroke and the IDI share is displacement. All other components are different including the rotating assembly, compression, cylinder head design, injection system (direct vs in-direct), powerstroke uses a high pressure oil system to fire the injectors where the IDI uses fuel pressure directly from the injection pump... IDI is all mechanical where the powerstroke is all electronic.. etc..etc. It is a common misconception that they are similar when in all honesty, they are very different.

The only thing that I'm aware of that you can use on the IDI from a powerstroke is the turbocharger (which will not bolt on.. would have to build a custom kit for it to mount to).. and the connecting rods (which have to be machined on the big end as they are too thick to fit the crank however Justin Anderson offers the machining service.

Didn't intend to offend you if I did.. it is just a common misconception.

Jdawgsfanasty · 01-29-2018, 12:44 AM

Quote:

Originally Posted by Mr4btTahoe

The only thing the powerstroke and the IDI share is displacement. All other components are different including the rotating assembly, compression, cylinder head design, injection system (direct vs in-direct), powerstroke uses a high pressure oil system to fire the injectors where the IDI uses fuel pressure directly from the injection pump... IDI is all mechanical where the powerstroke is all electronic.. etc..etc. It is a common misconception that they are similar when in all honesty, they are very different.

The only thing that I'm aware of that you can use on the IDI from a powerstroke is the turbocharger (which will not bolt on.. would have to build a custom kit for it to mount to).. and the connecting rods (which have to be machined on the big end as they are too thick to fit the crank however Justin Anderson offers the machining service.

Didn't intend to offend you if I did.. it is just a common misconception.

Not offended at all...I can always learn...

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Mr4btTahoe · 01-29-2018, 09:26 AM

Lol.. can't we all.

Jdawgsfanasty · 01-29-2018, 11:57 AM

Quote:

Originally Posted by Mr4btTahoe

Lol.. can't we all.

Only the smart folks...the rest know it all

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MengerMayhem · 01-29-2018, 12:20 PM

Awesome info guys! I have done some reading on on the 7.3idi . I do live next to an auto salvage yard out in the country, is it worth getting a turbo off an early f250/350? and fabricate a system. I come from from motorsports industry for the past 10 years as a mechanic (Motorcycle/atv) and during that time I worked on the cummins 6bt engines with a marine set up on the houston ship channel for like 2 years. I've rebuilt plenty of engines over the years just never a v8 or v8 diesel for that matter.
The power is lacking for sure as of right now. 55mph down hill with the wind to my back and 40 "up hill" and a "hill", is what east texas has to offer.
I am interested in alternative fuels and possibly making it myself in the future.

As far as what I'm looking for in power, is safe Hwy speed, tow something like a 1500 truck and BE RELIABLE.
Im thinking i can achieve it by cleaning/tuning up what I have and adding a turbo. Not really pistons and cam if i don't have to. but will.

I think i might need a trans with overdrive but not sure what the rear diff gear ratio is or what it should be.

You guys are great and make this project not so overwhelming!

Jdawgsfanasty · 01-29-2018, 12:28 PM

Quote:

Originally Posted by MengerMayhem

Awesome info guys! I have done some reading on on the 7.3idi . I do live next to an auto salvage yard out in the country, is it worth getting a turbo off an early f250/350? and fabricate a system. I come from from motorsports industry for the past 10 years as a mechanic (Motorcycle/atv) and during that time I worked on the cummins 6bt engines with a marine set up on the houston ship channel for like 2 years. I've rebuilt plenty of engines over the years just never a v8 or v8 diesel for that matter.
The power is lacking for sure as of right now. 55mph down hill with the wind to my back and 40 "up hill" and a "hill", is what east texas has to offer.
I am interested in alternative fuels and possibly making it myself in the future.

As far as what I'm looking for in power, is safe Hwy speed, tow something like a 1500 truck and BE RELIABLE.
Im thinking i can achieve it by cleaning/tuning up what I have and adding a turbo. Not really pistons and cam if i don't have to. but will.

I think i might need a trans with overdrive but not sure what the rear diff gear ratio is or what it should be.

You guys are great and make this project not so overwhelming!

I wish I knew motors

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Mr4btTahoe · 01-29-2018, 12:51 PM

How many miles/hours are on the current engine?

What RPM are you turning at what speed?

As far as pulling a turbo from another IDI, the charger, pedestal, valve covers, etc should be usable. The CDR valve is typically relocated from the back of the intake manifold to the valve cover or front timing cover when a turbo kit is installed. Most of the kits put the turbo on a pedestal just behind the intake manifold.

You can make reliable power pretty easily. If the engine has lower miles, I'd say head studs, a 90cc or so injection pump and a ATS 093 turbo kit (or one from R&D) and it'll make for a healthy boost in power output and be reliable doing it.

Justin is a great guy.. you can call him directly and let him know what you are shooting for and he'd be glad to help point you in the right direction.

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