18RG Woes

[FrAsErTaG]

Hi All

I am new to the forum.
I recently purchased a 1980 RA40 Celica that has an 18RG engine in it.

The 18RG has had headwork done (port,polish,shave) and is also running high lift cams, it has twin solex carbs, extractors.

The car had been sitting for estimated 6 years in a car port before I made the purchase of it.

The car had a busted mechanical fuel pump, I started it in the driveway of the previous owner using a gravity fed hose and funnel to the twin solex carbs
She started up and once warm idled nicely (lumpy cam but nicely)

I was able to put registration (3 months every 12 months was placed onto the car) on the car and drive it home (1 street away )

Since getting the car home, the fuel pump was replaced, battery replaced.

With these changes the car started and ran, I went to the service station and filled it up with some fresh fuel and added air to the tyres.

I drove it for around 5 minutes taking it easy and it seemed fine, there is a switch inside the car to power the thermo fan at the front and this is operating correctly and temp sits just a little lower then half.

Drove the car home.

Next day dumped the oil, changed oil and filter.

Car seems to be running really well, another short 5 minute drive around the block.


I put some insurance on the car and attempted driving it to a mates place as he is a celica buff... approximately 10km away.
Upon driving there, the car started to miss a bit... I tried giving it a bit more or bit less to see if there was a sweet spot... It progressively got worse until the car was running on three cylinder. This was around 2-3km from my house... I turned around and limped the car home.

I have no real knowledge of the solex carbs and its been a decent while since ive owned an "old car" and why I am seeking some advice before I go down the path of throwing money at the wrong problem.


The car usually starts up on all 4 after it has been left sit for a day or so... but once you attempt driving it, it starts to bug out and miss and stop firing on number 4.

I have so far done the following:
Changed spark plugs, same model as what was in the engine. BPR5EA-L gapped the same, I think .8mm
Changed the Distributor cap (had some wear and tear), changed the rotor (had scuffing and was brittle)

The above made no difference.
Cylinder number 4 is the one that is being effected, When I remove the lead for number four I hear the lead arching even when the end is not near metal? should this be happening?

I tried swapping 3 and 4 at the engine and dizzy, Still number 4 fails to fire.

I tried spraying carby cleaner around the manifold<->engine,brake booster cable, dizzy vacuum line... with no distinctive change to idle.

There is no sign of water in the oil in the sump, there is no sign "milk" under the oil cap and there is no signs of bubbles within the radiator

I am not sure what to start with next, I do not really want to throw a whole heap of money at it...

My thoughts are that Number 4 is getting too much fuel and eventually the plug gets so wet it cannot fire. When I removed the old plugs they were very dark carbon but no signs of oil.


I do not currently have a compression tester or a timing light so will have to borrow these over the christmas break.


Any one got any ideas?
Should I try new points? new coil? new leads? the current leads look in good condition and whilst the car has sat for 6 years the leads look almost new, a lot of head work was done just before the previous owner stopped driving the car....




Thanks !!

[FrAsErTaG]

Nevermind

The problem has been diagnosed and corrected.

It was the main fuel jet for the 4th cylinder had come loose, carefully tightens and she is running smooth again.

[73GTV]

Nevermind

The problem has been diagnosed and corrected.

It was the main fuel jet for the 4th cylinder had come loose, carefully tightens and she is running smooth again.

Outstanding troubleshooting. Great job!!