Burn valve syndrome?

[yocka]

Hi all, new to the forum. Just bought my first Hilux! It's a 1983 model with a 2L petrol engine. When I strike it up from cold it sometimes cuts out until the engine is warm, it runs rough - sounds like it's only running on 3 cylinders - and smells of petrol fumes when the engine is running. It's done 365,000km, not sure of service history and the previous owner said it might have a burnt valve. I have sourced a re-con head to fit if I can find out for sure it's got a burnt valve on it. Does anyone know how I can check this please? Also, today I sourced some other HT leads as somebody told me to swap the leads about, and it seemed to run slightly better. So, do I give the truck a good service (i.e. new plugs, leads, dizzy cap, etc) and see how it goes or should I try something else? If anyone has any ideas I'd be grateful. Cheers, Leigh

[john253a]

you could ask around, and see if anyone will lend you a compression tester,
you remove the plug and crank it and see what you get
af all is good then i would go down the plugs, leads, button and cap
also being 83 is it points or not i cant remember, if so change them and condenser as well

but by what your saying and the kms its done idd say nilly time for a rebuild,

if you do decied to change the head, idd drop the sump, and replace the ring, bigends and conrod bearing + give the bore and light hone,

ive done this on a few engines, its not the correct way to do it but will increase the longevity of the motor and give it back most of it performance and economy

i done a 90mdl lux for my mate this way and the berings and rings were around $250 with gasket kit, head set up for gas, new plugs, rotor/cap ect around $1250

[toyboata]

A cylinder leak-down test is much better for diagnosing a burnt valve.
It's most likely on the exhaust valves but using a vacuum gauge is a good way to test for burnt/leaky intake valve. Reading should be steady. If the needle flutters then there's problems with intake valve/s.

[danmcccc]

compression test like what the others said...can tell you alot about a motor

[yocka]

thanks guys for the answers. i played about with the carb etc today and it made quite a different and seems to run alot better. gonna get some new plug leads
,dizzy and points etc 2morra plus get the timing done and take it from there.

also in time i might think about a engine swap. so what would be a good engine to use? not fussed diesel or petrol.

[danmcccc]

thanks guys for the answers. i played about with the carb etc today and it made quite a different and seems to run alot better. gonna get some new plug leads
,dizzy and points etc 2morra plus get the timing done and take it from there.

also in time i might think about a engine swap. so what would be a good engine to use? not fussed diesel or petrol.

3rz all the way

[yocka]

What sort of mods does this involve to fit?

[Ggn25]

Which engine is it . 2 ltr could be a 3y engine. 2y = 1.8ltr. 3y = 2.0 ltr and a 4y = 2.2ltr

Over the years I have seen a few issues, just to make sure you are not led down the grade path I will explain an issue hard to find.
On some "y" series engines they run an aux fuel pump diaphragm on the carby.this is in addition to a accelerator pump plunger, operates under vacuum. It is at the front of the carby and there are a few different models. It had a vacuum tube to it that will go to a vacuum switch in the inlet manifold - sometimes on the port to cyl 3 or even cyl 2 . This diaphragm can get a small hole in it letting fuel into that part of the manifold , enough to flame out the plug at idle and give a seeming dead cylinder. I even saw someone have a head reco done and it still missfired.

This can be easily check by removing the vacuum tube and see if there is fuel in it - petrol tastes like crap ,lol... This is all only if your engine is the correct series and if it has an aisin carby with this diaphragm , the diaphragm is a separate part to a carby kit and always gets overlooked.

Cheers Tim

[yocka]

hey its the 18r-c engine well thats what the badge says anyway. today i changed the plugs, dizzy cap/arm and points, runs better but still slight misfire. but still need to change leads and get the timing checked. just had a look at carb with regards to the aux fuel pump diaphragm i aint a clue what am looking for but i do see lots of vac pipes goin all different places.

[yocka]

UPDATE
timing done and setup correct, was running good after and all the way home. aint driven it till today since and now it has started playing up so bad now it wont start now. before it wouldnt start it was backfiring out the top of the carby and sounded like it was on 2 or 3 cylinders. so if anyone can help me out as am getting about pissed off now.

[toyboata]

Sounds like timing way out or leads not in correct order, but if that was the case it would not have run good to begin with. Dizzy could have cone loose and timing moved?
Points closed up maybe? Wouldnt cause backfire though.
Might be worth a trip to mechanic

[yocka]

Had a comp test done. Number 1 cyl 125psi. 2 cyl 65. 3 cyl 105. Cyl 4 110.
Am thinking of putting in another 18r engine in or something else? So am asking what else can I put in it with not to much hassle.

[fgk228]

I think you can get kits for the commodore engines from marks adaptors.

[helmut79]

Had a comp test done. Number 1 cyl 125psi. 2 cyl 65. 3 cyl 105. Cyl 4 110.
Am thinking of putting in another 18r engine in or something else? So am asking what else can I put in it with not to much hassle.

V8 FTW

[yocka]

Well my trucks parked up now so I have the time to get started with it. I would like to put a v8 in it. I am on a budget but only with parts etc can get most of fitting down at work