problem with a sohc to dohc conversion

[drifter1283]

hey i was just wondering if anyone could help me i have 89 coupe with a sohc and installed a 90 dohc from a hatch back, and i was reading the threads about wiring and how you just match the colores and the ones that dont match you dont do anything with. so i did that and everything is good but the engine wont turn over, it almost did one time, i check the fuel pump and it was working fine so it is gettig fuel. so then i thought i wired ti wrong or somethign but it wasn't so . so then i checked the ignition coil and it was working just fine so. do you guys have any idea of what it might be, the car has been sittign in my drive way for about a year, and i really want to get it up and runnin. thanks

[nomore240sx]

there isnt a 90 dohc. 90 had sohc. 91 above had dohc. Check your sparks and timing. Also your ignition coils and such. Just make sure you are getting a spark from the spark plugs.

[drifter1283]

well the car i got it from was in the junk yard and it said it was a 90 so i figured it was like a december model or something , uh yeah i cheked all that stuff already thats why im kinda frustrated

[drifter1283]

do you think it might be something internally?

[_/_/_/M aurice]

Let's think for a second. If the motor isn't turning then it doesn't matter that you are apperently getting fuel.

Is the battery and working? If so, maybe the starter is toast. Just hooking up a few wires won't determine whether or not the car will run.

Make sure to check all grounds (there should be 2 or 3, I don't remember at the moment)

I also hope you are using the harness and ECU from the DE. And a word of warning - your SOHC tach won't work.

I'm in the process of writing up a SOHC-DOHC FAQ because I see a lot a problems lately with them. Myself and a friend seem to have to only working ones I know of...

[drifter1283]

well yeah the battery and starter work( the starter and tranny are both from the ka24e) ill turn the key and the motor turns but it wont turn on its really anoying, and the harness is from a 92 240 and i have sevral ecu's there numbers are 26, 28, 30 and 14 the 14 is from the soch, i thought i toasted the ecu's so i went out and bought a bunch

[_/_/_/M aurice]

The bloddy DOHC is one finicky SOB. Mine did almost the same thing as you describe. Let me know if your plugs are getting wet. If not, then do what I did and maybe by the same strange miracle that came to my car, yours will also work. What I did was take apart the fuel rail. Unhook the hoses (make sure that the return hose is where its supposed to be, etc.) and try cranking. I still have no idea what fixed mine, but taking all that apart seemed to do something...

Good luck, and keep me posted.

[drifter1283]

ok this is what i did i went and got another fuel rail and injecters from another 240 and it still wont start, do you think the fuel lines are switched around?

[drifter1283]

yeah the plugs dont seem to be getting wet but the pump does work i cranked it for over a minute streight and there almost dry. actually they are dry

[_/_/_/M aurice]

It could well be the lines. Mine seemed to have a big air bubble in it...

[drifter1283]

so how do i fix that? well im checking the line but im not sure if the return fuel line goes on top or on the bottom.

[_/_/_/M aurice]

Well, after cranking for a moment try *carefully* to take off a flex line. Cover your eyes because if the fuel pump is working it will be under some decent pressure.

Mainly its just trial and error, thats the last thing I did before it started for me. So if that doesn't work, all I will be doing is guessing.

BTW, do you have MSN? It'd be a lot easier to discuss through there.

[drifter1283]

no i have aim

[_/_/_/M aurice]

boo, get MSN or keep suffering. lol, I'll help out as best I can, but I'm going to go watch some Option vids, so I'll check posts later.

[drifter1283]

alright awesome dude thanks