Please help! Been fighting with my supra for 2 years!

[86ts6m]

Alright everyone. I'll give you the smallest run down I can on my issues. It has for the most part been with Idle and starting.
I purchased my 86 comp 2 years ago and got a hell of a deal knowing a few small things were wrong mostly cosmetic. Ran the boat for the first part of the summer last year and ran ok. Midway through summer everything started going wrong.
Driving after/pulling a skier at under WOT and randomly would die.
Not a big deal try and start her back up and no start. Try feathering the gas and get her limping back to the dock. Multiple times having starting issues and attempts at leaving the dock have failed. Thinking it was a carb issue was planning to replace the edelbrock 1409 carb the next year. I tried replacing the first fuel filter attached to the stringer in the bilge. Nothing looked clogged or dirty. Pulled the boat out of the water for the winter and winterized.

This spring I un-winterized the best I could and could not get the boat started for the life of me. I pulled the dizzy cap and replaced with the ignitor II electronic ignition, new spark plugs correctly gap, new coil 45k volt coil from pertronix, new cap. Before I replaced everything I was not getting any spark. Now I get spark but it is extremely hard starting the boat. Hot or cold... now I can get the boat started if I crank it and give it all the throttle I can in neutral. It idles horrible if I let off the throttle, and it dies almost immediately especially if I have to put the boat in gear. I have to feather the gas and quickly put it in gear and hope it doesn't die.
Got frustrated and ordered a new 1409 edelbrock thinking that it was just a dirty carb and I would have an extra if I rebuild the old one. But it still runs like crap! Still hard starting and will not idle below 1000 rpms. Again it idles amazingly over 1200rpms. I checked the fuel pressure at the pump and it was around 5.2psi which I believe is normal. My edelbrock says no fuel pressure over 6.5.... I can not for the life of me figure this out. Please help

1986 Supra comp Ts6m
Ford pcm 351

I replaced
New 1409 edelbrock carb
New autologhts 24s gapped to .035.
New cap
New rotor
Electronic ignition
New coil
New water/fuel filer
New inline fuel filter right by the carb
New batteries

[Salty87]

Starting and idling issues suck! Can't help as I've never done the electronic ignition conversion but ballast resistor issues come to mind and/or maybe timing.

Lots of peeps here can help so sit tight.

Welcome to the board.

[NorCalPR]

Has the compression been tested?

Fresh fuel or are you certain the fuel is ok?

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[michael hunter]

Is your engine at an angle tipped to the rear or is it level?

[jasun]

I vote for a timing issue. Did you just replace the Dist Cap or the whole dist? When I bought my salt it would start but then wouldn't run unless it idled at 1500 rpm. thought it was the carb and I changed out the Holley for an Edelbrock but still didn't fix it. Ended up one of the springs on the dist was bad or broke... was not advancing as it should have. replaced the whole distributor with a:
PNX-D200800
Distributor, Marine, Plug and Play, Magnetic, Mechanical Advance, Black Cap, Chevy, Big/Small Block, Each
(Mfr. #: D200800)

Ran like a champ after that.

If you can take your distributor apart check for any broken or bad springs.

What is your timing set at?

[86ts6m]

I upgraded to an electronic ignition that clearly stated taking out the ballast resistor. Pertronix ignitor II. Timing was roughly 10. When I checked it. But that was at 1000+rpm any lower and we couldn't get it running.

[86ts6m]

Has the compression been tested?

Fresh fuel or are you certain the fuel is ok?

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Compression has not been tested since I bought the boat almost 3 years ago now. I could be wrong but the engine runs amazing over 1200 rpm, Without a hick up. The boat idles so rough that the engine sounds like it's a Diesel engine. When I get on the throttle it purrs like a kitten.

As for fuel. The boat during last summer was used when it wanted to cooperate so fuel was changed multiple times. I did put stabilizer in it while winterizing. And filled the tank up. The problem is not new, so I didn't think it would be because of gas.

[86ts6m]

Is your engine at an angle tipped to the rear or is it level?

The engine is level when it sits in the water. Only angled slightly if that.

[NorCalPR]

Hm. How many turns out on your fuel screws? Float height set?

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[86ts6m]

I vote for a timing issue. Did you just replace the Dist Cap or the whole dist? When I bought my salt it would start but then wouldn't run unless it idled at 1500 rpm. thought it was the carb and I changed out the Holley for an Edelbrock but still didn't fix it. Ended up one of the springs on the dist was bad or broke... was not advancing as it should have. replaced the whole distributor with a:
PNX-D200800
Distributor, Marine, Plug and Play, Magnetic, Mechanical Advance, Black Cap, Chevy, Big/Small Block, Each
(Mfr. #: D200800)

Ran like a champ after that.

If you can take your distributor apart check for any broken or bad springs.

What is your timing set at?

Myself and a buddy got our hands on a timing light and checked and had it set at around 10. This sounds mostly like my whole problem. When I installed the EI I looked in the bottom of the distributer and it was rusty and looked a tad dirty but I didn't see those 2 springs broken at the bottom. Again we didn't replace the whole dizzy, just new cap, rotor that came with the EI and plugs. I am going out of town till the 23rd, and the lakes and rivers on the chain o lakes here in Antioch IL are at record highs. 100 year flood they are saying. Hopefully when I get back into town I can pull the cap off and look at the dizzy more in depth.

[86ts6m]

Hm. How many turns out on your fuel screws? Float height set?

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Brand new edelbrock 1409 carb I didn't think to check float height on a brand new one since they are set from the factory. The old 1409 that I had on there had the same issues I'm having now. Idle mixture screws are both set at 3.5 turns, again that was rough bc I couldn't get the boat to idle and set my idle screw correctly.

[NorCalPR]

Idle screws sound very far out. Id try 1.5 turns out from seated on both and go from there.

Double check float height. Its dead nuts easy on those.

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[michael hunter]

When its running bad try putting your hand over the primary bowls of the carb . Not to seal it off just to limit the amount of air going in . If it runs better you are too lean if its worse or the same try pulling the PVC valve and allowing more air in see how it runs then.

[supra790]

I had problems with my 87 Sunsport running at idle speeds. I tried a new carb and all kinds of other stuff...finally a mechanic at the lake noticed my intake manifold was the problem. It was a high performance manifold designed to race at high rpms. I replaced it with an original manifold and it instantly fixed all the problems

2016 Supra SG 450

[jasun]

Any update?


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[86ts6m]

Any update?


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Just got into town from vacation on Monday drove up to the lake house today to find that the water high still hasn't receded enough to get to the boat. The flooding on the fox river and chain o lakes have been the worst in 20 years. When the water levels go down enough to get to my boat I will check everyone's diagnosis. I really do appreciate everyone's input, time of all this rain doesn't help my cause in northern Illinois.

[Jetlink]

Just got into town from vacation on Monday drove up to the lake house today to find that the water high still hasn't receded enough to get to the boat. The flooding on the fox river and chain o lakes have been the worst in 20 years. When the water levels go down enough to get to my boat I will check everyone's diagnosis. I really do appreciate everyone's input, time of all this rain doesn't help my cause in northern Illinois.

Where on the Fox are you at or I guess where is your boat at is a better question? Are you above or below the dam?

[86ts6m]

Where on the Fox are you at or I guess where is your boat at is a better question? Are you above or below the dam?
Above we are up on channel lake on the chain, in Antioch. But I live in cary.

[86ts6m]

I vote for a timing issue. Did you just replace the Dist Cap or the whole dist? When I bought my salt it would start but then wouldn't run unless it idled at 1500 rpm. thought it was the carb and I changed out the Holley for an Edelbrock but still didn't fix it. Ended up one of the springs on the dist was bad or broke... was not advancing as it should have. replaced the whole distributor with a:
PNX-D200800
Distributor, Marine, Plug and Play, Magnetic, Mechanical Advance, Black Cap, Chevy, Big/Small Block, Each
(Mfr. #: D200800)

Ran like a champ after that.

If you can take your distributor apart check for any broken or bad springs.

What is your timing set at?
18308

This is that the dizzy looks like on the inside. No broken springs... one is rusty but when I push it open they spring back to normal...

[86ts6m]

I had problems with my 87 Sunsport running at idle speeds. I tried a new carb and all kinds of other stuff...finally a mechanic at the lake noticed my intake manifold was the problem. It was a high performance manifold designed to race at high rpms. I replaced it with an original manifold and it instantly fixed all the problems

2016 Supra SG 450
18309
Looks to be a stock manifold ...

[supra790]

18309
Looks to be a stock manifold ...
Yes it does. Good luck with it...

2016 Supra SG 450

[Jetlink]

This is that the dizzy looks like on the inside. No broken springs... one is rusty but when I push it open they spring back to normal...

I am hoping to get to mine and address a rough idle and overall lackluster performance on my Comp this weekend. Ditching the points and going electronic, kit is already in hand, just need to install and get it going.