vibration and overheating at gm 350 (one piece rear seal carburated)

[sarantis]

Re: vibration and overheating at gm 350 (one piece rear seal carburated)

Don S you guessed right,i had difficulty putting the base initial timing mode.I'll use your info thanks.Now what about my previous question?

 

[Don S]

Re: vibration and overheating at gm 350 (one piece rear seal carburated)

Which previous question? if you are referring to dropping back to 6? instead of 8? for initial timing, you might want to make sure you have it set right and working. Be sure to check your advance timing after taking it out of base timing mode.

 

[Bondo]

Re: vibration and overheating at gm 350 (one piece rear seal carburated)

cut it back ? you mean to reduce to 6*? i thought that with the hi octane gas i could go to 10 degrees.Wrong impression?
and the 8* is at 650rpm?
(as described above the heads have smaller combustion chamber,so higher compression ratio and the experts here advised me i should run hi octane gas)?

Ayuh,... Most SBCs will run at 10?, but as noted, You don't have Most SBCs...
With the small chamber heads, the Best you can do is Start somewhere,+ Try It...

As I said before, be very careful of Detonation...
Regardless of the Hi-test gas, it Might run OK at 10?, or it'll Detonate...
It might run at 6?, or it might Detonate...
You might even have to run it lower,... Donno...

Due to your somewhat Custom motor,... You'll have to Carefully tune it....
Just be well aware that Detonation will reduce your brand new motor to an Anchor in No time flat....

 

[sarantis]

Re: vibration and overheating at gm 350 (one piece rear seal carburated)

This new Delco Voyager est drives me crazy.I start the engine ,i put into the distributor the connector with the white looped wire and the black wire with the 12V.The rpm gets lower,i say good sign ,now it's unlocked to put the initial timing.i change the RPM and the advance stays steady.Again ok and i go on.I turn the adjusting Knob at my timing light at 8* and i shoot the balancer.i adjust the distributor until the two notches(the moving at the damper and the steady)are aligned.i Take out the connector and the rpm gets higher.I set the rpm 800 and i turn the knob until the two notches are aligned .I look at the knob and to my surprise it shows 24 degrees(or 20 if i don't remember well).The curve diagram at 350'service manual starts at 800 with 8 degrees.What is going on here?I wonder what is the meaning of the initial timing ?Isn'it the same if without the connector tool turn the distributor and put it directly to 800rpm-8degrees?Searching google i came up with a delco pdf that said that delco est gives 8* at 500 rpm.Before Don S send me the instructions i started two times the engine with the 12V of the connector tool hooked up but i can't believe i did damage to the electronic module of the distributor.Please help.

 

[Don S]

Re: vibration and overheating at gm 350 (one piece rear seal carburated)

If it's showing 20 to 24?, then when you disconnect it, it's going to full advance.

It only takes once to have it hooked up wrong to damage the module. Sometimes you can get away with it, sometimes you can't. Sounds like you weren't one of the lucky ones. Could also be that the module was bad from the beginning. I've pulled them out of the box and they didn't work.

 

[sarantis]

Re: vibration and overheating at gm 350 (one piece rear seal carburated)

Don S now you brake my heart.I want to make some more efforts to see if it reacts.Is something wrong if i try to bring it to 800rpm-8* and then raise rpm to see if the advance gradually increases?

 

[sarantis]

Re: vibration and overheating at gm 350 (one piece rear seal carburated)

i mean without using the connector tool

 

[Don S]

Re: vibration and overheating at gm 350 (one piece rear seal carburated)

I don't know what to tell you. On V8 engines, when you disconnect the timing tool, they stay fairly close to what you set them at. But the do bounce around a lot. Usually from 0 to 15? BTDC. then when you rev them up without load they will steady up and go on up to max timing.If you are getting max timing at idle, your module is either the wrong one, or damaged in some way.

 

[sarantis]

Re: vibration and overheating at gm 350 (one piece rear seal carburated)

Finally i think the Delco est is ok.Possibly testing it without load gave me wrong impression.I went for a run.The boat runs good but after planning it starts overheating again.So i 'll focus on two things that i believe hide the solution of the problem.
1)Starting at the dock and inspecting the clear hose from the hydraulic steering's cooler to the thermostat housing, at the beginning the hose is full of water but after a while litle by litle an air buble stream is coming up and gets biger as the engine is going to the operating temp.Even then i 've counted the water volume and is according to the manual exept a possible deviation due to the rpm.When on plane the clear hose is full.But i can't believe that the above situation is normal.Exactly the same with the old outdrive.I' ve also replaced the rubber hose and inspected the bell housing for any possible escape of gases to the incoming water passage (near the o-ring )but i couldn't find anything.
2)As almost the only thing that hasn't been replaced and examined is the y-pipe i suspect partially freezed shutters or the pipe to be clogged by them but it's a nigtmare to take the boat out ,the engine out and check (unfortunately at this pre alpha set up the shutters are at the bottom).So,unless you can suggest me something the only thing i can think about is:
in my setup the water comes out only through the elbows.Between them and the ex.manifolds there is a vented plate.So i take out the elbows ,i tap the pipe and i make another thicker plate with opening at the center for the gases and a small pipe adjusted at the place of vent hole.I will extend the elbows' hoses and lead them aft out of the boat.The height diference is about 15-18 inches. i think this test tell much.Please your opinion