Harvey Wheeler

SR5 TACH wiring help... So converted my 88 Pickup 22RE to run on propane with kit from Gotpropane. Install is going good and now just have to finish up some plumbing issues. My question is I have an SR5 gauge cluster in the truck and I am not sure what wire I need to hook into to get the tach to work? I installed a DUI distributor when I did the conversion so I removed the factory coil and distributor. To power my new DUI distributor/coil combo I tied into the hot wire from the old distributor plug (key on 12 volts). There is another wire on that plug that is not hot so I am thinking that will send the signal to the tach but just was curious if anybody knows for sure? The DUI instructions state several places that hooking the tach terminal to anything else will/can mess it up. Any help?

millball

Most ordinary distributors just wire an aftermarket tach to the distributor side of the coil, but I don't know if that's how a Toyota factory tach works.????
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But...What's your reason for converting a fuel injection engine to propane????

I sure understand the motivation to convert to propane from carburetor equipped, as I have suffered from carb limitations in offroad situations since I started 4wheeling more than 40 years ago.

Harvey Wheeler

I am converting to propane because my EFI system is showing 30+ years of wear and tear from the lovey Michigan climate I live in (salt and 20 to 40 deg temp changes on a regular basis). There was a great amount of corrosion in the wiring harness where Toyota crimped the fuel injection signal wires (not their best wiring idea BTW)... but the final coup de grace to my EFI system was mice deciding to have a picnic in the harness. After changing the computer, splicing wires and every other system I decided to remove all that and go propane. I would love to keep my SR5 tach though its sweet!

se7enine

iTrader: (2)

Wire your Tach signal to the back of the cluster or directly to the cluster connector.


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Harvey Wheeler

Thank you for the pictures very helpful. I was able to figure it out. The one green connector on my truck that hooks up to the coil has a black wire with red line and a black wire with red dots (from harness running from the drivers side). The black wire with red line is hot with key on and cranking. The other wire is the tachometer signal. I put a male end terminal in both and the coil works as does my tach! Attached is a link to a short video I shot explaining it.

Harvey Wheeler

Another video showing how I mounted the tanks and ran the propane lines. First impressions after conversion: THUMBS UP!
Overall I would say the low end power is much better than the EFI system. The throttle response is perfect and the engine now can "lug." I tried to find the "stalling point" just playing around and I could not get it to stall. Not saying it is un-stallable just now it will chug down to around 300 rpm, but I don't recommend lugging an engine that low I feel it is hard on them not to mention not much oil pressure that low... FYI first starting of the day you have to let it crank about 10 to 15 seconds to "prime" the intake not a huge deal, but in Michigan I better make sure my battery is charged up and the CCA's are up to the task on a 0 deg day... Anyway, the only downside I see so far (disclose: I am still messing with timing trying to find the "sweet spot") is I notice significantly less top end pulling power from 45mph + compared to EFI with gas. It will get up to speed, but it does take a little longer. I don't consider it to be a big negative Toyota pickups where never a race truck anyway and I learned from my research that I would be loosing some top end. I am currently researching putting a turbo on it to counter this downside (low top end) but most likely will wait till spring and warm weather to install. Considering, however, my truck was totally disabled after mouse damage and corroded wiring. I considered getting rid of it after owning it for 25+ years this propane system has "breathed new life" into the truck... Would I have done this conversion if the stock EFI system was still operational? No most likely not, but I would do it if I had a carburetor 22R engine or issues with the EFI system for sure! In fact my Dads old 86 farm truck is having some carburetor issues so I might do the dual fuel conversion to it.