Start up troubles

Any type of technical questions or info

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Tezrota
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Start up troubles

#1 Post by Tezrota » Thu Aug 02, 2018 2:49 pm

Hi all i started my 13b half cut bp for the first time
But im having issues with it running

Here goes

Running series 3 dissy with j109s
And for now a 48mm idf (looking for ida😀)

Holley fuel pump
It starts first pop with a couple wide open squirts of fuel.
But it wont idle at all.nothing under 4000rpm then dies if i stop pumping the fuel.
Is it regulator issues i wound it right out and tried it wound right in.
I can see the flow of fuel just stop coming out of jets then it dies.

Also i have 80psi oil pressure.about 88° temp when i kept it running.
I have tightened up all the manifold fir leaks etc.

Any help would be appreciated .

Tezza

Tezza.ferg@hotmail.com
0472700359



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Re: Start up troubles

#2 Post by bumpstart » Fri Aug 03, 2018 12:44 am

timing ., half bridge will want a modded dizzy, regraphed for 15-25 degrees or locked, and placed around 22 BTDC


also float level . google . fuel pressure. 4psi
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Rota_Motor (Sat Aug 04, 2018 10:28 pm)


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Re: Start up troubles

#3 Post by Rota_Motor » Sat Aug 04, 2018 10:31 pm

bumpstart wrote:
Fri Aug 03, 2018 12:44 am
timing ., half bridge will want a modded dizzy, regraphed for 15-25 degrees or locked, and placed around 22 BTDC


also float level . google . fuel pressure. 4psi
So, will insufficient static timing setting make it hard to start if ported? My 1300 was always hard to start with BP 12A and standard carb, timing was set to standard as per the engine I pulled out and only available info I had at the time being the workshop manual.

I always suspected low compression as it would wind until it started to fire and wind faster and faster until it caught properly and threw the starter out. Also idled very smooth for a BP, finger in the ports says it is definitely BP though.


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Re: Start up troubles

#4 Post by AlWanga » Sun Aug 05, 2018 8:48 am

I had the same problem with my 12A full cut Bridgeport I built last year which is running a nikki still. When it was set too far retarded it pretty much had no brap brap sound and would not idle at all.

It ended up being the timing which I solved by locking the dizzy and setting at 20 degrees. It now idles fine at around 1850 rpm. The only problem with doing that is mine is now a pig to start, especially when cold.

Before locking it I just advanced it as far as I could go without any getting detonation and it then idled fine as well

I am now going to see if I can either buy another dizzy that has been re-graphed so that it has full advance once started but no advance whilst starting, or hire someone with the skills to do it.


Wanted Re-graphed dizzy (not locked) for 12A Bridgeport or someone who can modify mine

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Re: Start up troubles

#5 Post by pknoutrx2 » Sun Aug 05, 2018 7:39 pm

For what it’s worth I’ve found they start and idle fine on standard timing. Brap away nicely too.
If it doesn’t idle down around 1200 could be spark, mixture, comp or back pressure in exhaust. Or a combination.
Think they run ok with standard timing but may need to limit advance so it doesn’t ping. And they do.
Noticed a few race cars on you tube with too much advance you can hear it once you have experienced it.



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Re: Start up troubles

#6 Post by RX7_BEN » Tue Aug 07, 2018 3:58 pm

Just throwing my 2c in there as well.
I've run a bunch of full cut bridgies over the years with a bunch of different timing arrangements.
Never had a starting issue with a locked dizzy set at 20-25 degrees advance.

I'd say look elsewhere, as timing is not your problem Mr alwanga.



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Re: Start up troubles

#7 Post by AlWanga » Tue Aug 07, 2018 6:28 pm

Thanks for the comments guys, I am now at a loss with mine as playing around with the timing gave various results without touching anything else. I will go back to the drawing board.

Sorry Tezrota for stealing your post. I will be very interested to see how you solve your problem so please post when you get it sorted.

Cheers

Al
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Tezrota (Thu Aug 09, 2018 4:37 pm)


Wanted Re-graphed dizzy (not locked) for 12A Bridgeport or someone who can modify mine

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Re: Start up troubles

#8 Post by Tezrota » Thu Aug 09, 2018 4:37 pm

Haha all good standard hijack lol
Nah that's what forums are for
So got it started .was out a tooth.
Pulses great at 1200rpm

But im having temp issues
New radiator
Bew water pump
New thermostats
Got one 9 i ch fan running for now

I shut it off as soon as it hits 95°

Could the gilmer be cavitating?



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Re: Start up troubles

#9 Post by pknoutrx2 » Fri Aug 10, 2018 4:34 am

Could be a combination of the gilmer pulleys turning water pump at crank speed instead of the speed that it was engineered to spin, which is nearly double crank speed.
And
Too small of a fan to cool the radiator, especially if there is no shroud to allow air pulled by fan to cool the entire core.
This makes a huge difference in itself, even if the rest of the system is in good order and more than likely the bigger problem.
In reality the ported engine will require more cooling capacity than standard engine but seems what you have is less than a standard cooling system. Not trying to be harsh just comparing what you have to a shrouded viscous engine driven fan.
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Tezrota (Fri Aug 10, 2018 7:59 pm)



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Re: Start up troubles

#10 Post by Tezrota » Fri Aug 10, 2018 8:11 pm

Sorted .
Wasnt actually getting that hot and i was shutting it down before the thermostat could function.
The sender was new .
Location at the back of the pump housing .
For whatever reason it just wasnt sending thenright temp.tapped a hole in neck and it came up to temp and coolings fine
Ran it for 10mins at 1300rpm and sat at 55-60°



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