I thought I would share my latest hobby experiment and experiance with everyone so that hopefully some one may also learn somthing new and possibly even usefull from it as well!
I picked up a 1987 Mazda B2600 extended cab 4x4 for $200 a while back with what the owner thought was a bad engine due to his having very little mechanical skills or knowledge.
Some of you may already know I have been custom building and running dual fuel systems on my pickups for many years now but this is my first full buildup of a dedicated propane fueled engine.
What I started out with was a somewhat mechanically neglected 1987 Mazda B2600 extended cab 4x4 pickup. Originally it used an overly complicated and unreliable emissions compliant electronic carburetor system that was typical in the mid 1980’s. That particular design Mazda used was impossible to tune properly or keep in tune and was an overall more of a waist of fuel and engine power than a gain to anything. What I did for the full propane conversion was to remove the entire emissions system from the truck and replace it with a simple single barrel vapor carburetor throttle body that came from an old propane powered combine engine I found at the scrap yard. All the old combine throttle body needed to work was some minor bolt pattern rework to make it physically compatible with a modern Woodward vapor mixer that attached to the top of it. It’s the same setup as the vapor carburetor systems used on propane powered forklifts.
To start out I removed everything that was emissions related in the vehicle, the smog pump, evaporative emissions control unit, the multiple vacuum control units and lines, the crappy electronic carburetor, the catalectic converter, and the rest of the rotted out and undersized exhaust system. All of this was reduced down to a simple all mechanical propane carburetor and vaporizer unit and the now unrestricted 2 inch exhaust system.
For the full propane conversion of an engine there is only one moderate mechanical modification that needed to be done and fortunately due to the previous owners neglect and all thumbs maintenance attempts this became the perfect vehicle for this type of conversion. At some point the previous owner overheated the engine and blew out the head gasket between the #3 and #4 cylinders but apparently decided to try and keep driving it until it burned a large gouge into the aluminum head. Once that happened the engine could no longer be repaired just by putting in a new head gasket. He decided to scrap the pickup which is where I found out about it and bought it for $200!

I picked up a 1987 Mazda B2600 extended cab 4x4 for $200 a while back with what the owner thought was a bad engine due to his having very little mechanical skills or knowledge.
Some of you may already know I have been custom building and running dual fuel systems on my pickups for many years now but this is my first full buildup of a dedicated propane fueled engine.
What I started out with was a somewhat mechanically neglected 1987 Mazda B2600 extended cab 4x4 pickup. Originally it used an overly complicated and unreliable emissions compliant electronic carburetor system that was typical in the mid 1980’s. That particular design Mazda used was impossible to tune properly or keep in tune and was an overall more of a waist of fuel and engine power than a gain to anything. What I did for the full propane conversion was to remove the entire emissions system from the truck and replace it with a simple single barrel vapor carburetor throttle body that came from an old propane powered combine engine I found at the scrap yard. All the old combine throttle body needed to work was some minor bolt pattern rework to make it physically compatible with a modern Woodward vapor mixer that attached to the top of it. It’s the same setup as the vapor carburetor systems used on propane powered forklifts.
To start out I removed everything that was emissions related in the vehicle, the smog pump, evaporative emissions control unit, the multiple vacuum control units and lines, the crappy electronic carburetor, the catalectic converter, and the rest of the rotted out and undersized exhaust system. All of this was reduced down to a simple all mechanical propane carburetor and vaporizer unit and the now unrestricted 2 inch exhaust system.
For the full propane conversion of an engine there is only one moderate mechanical modification that needed to be done and fortunately due to the previous owners neglect and all thumbs maintenance attempts this became the perfect vehicle for this type of conversion. At some point the previous owner overheated the engine and blew out the head gasket between the #3 and #4 cylinders but apparently decided to try and keep driving it until it burned a large gouge into the aluminum head. Once that happened the engine could no longer be repaired just by putting in a new head gasket. He decided to scrap the pickup which is where I found out about it and bought it for $200!
