Jump to content

Welcome to 205GTIDrivers.com
Register now to gain access to all of our features. Once registered and logged in, you will be able to create topics, post replies to existing threads, give reputation to your fellow members, get your own private messenger, post status updates, manage your profile and so much more. If you already have an account, login here - otherwise create an account for free today!
 
 

Photo

Carb Conversion Problems


  • Please log in to reply
23 replies to this topic

#1
unariciflocos

unariciflocos
  • Drivers+
  • 706 posts
Joined: 27 Oct 2008
  • Name:Andrei
  • Location:Freiburg, Germany
Garage View Garage
I have a 205 Rallye DFZ. I've changed the head to a D9B ported and polished, 11.5 CR, Kent PT23 and I'm almost done with the Inlet manifold for GSXR 1100 Mikuni carbs.

After everything was in place, except carbs, I wanted to see if electrics were ok so I turned the ignition and got nothing. I heard some relays turn, the fuel pump went on but the starter motor wouldn't engage the flywheel or turn.

I kept turning the ignition on and off and got the starter motor to turn for a fraction of a second two times. After that i would turn the ignition again and the fuel pump wouldn't turn on again. I changed the battery, I checked the wiring and everything seems to be ok (battery, alternator, starter motor are properly connected; all connectors related to the injection system are not connected). At one time the ECU went crazy and dash dials were twitching.

I really can't find a pattern or a possible cause. Sometimes the fuel pump turns on, most of the times id doesn't. What am i supposed to do with the ECU now that I've switched to carbs? What could be the problem with the engine not starting?

Thanks,
Andrei

(I know my explanation is a bit confusing but I'm still hoping some of you can understand and maybe help :D )

#2
hodgy

hodgy
  • Drivers
  • 485 posts
Joined: 19 Jan 2006
  • Location:Leeds, W Yorks
you dont need the ecu anymore now so you can throw it away

what have you done with the fuel pump? used 2 regulators to bring down the pressure or used a fascet pump and filter king?

#3
MrG

MrG
  • Drivers
  • 1,679 posts
Joined: 23 Dec 2007
  • Location:Soham, Cambridge
disconnect the ecu at least.

I just removed the ecu, and the injectors etc, left the wiring there bagged up and out of the way (I'm afairy where wirings concerned) and fitted the carbs.

#4
unariciflocos

unariciflocos
  • Drivers+
  • 706 posts
Joined: 27 Oct 2008
  • Name:Andrei
  • Location:Freiburg, Germany
Garage View Garage
I picked up my inlet mani today and will be mouning the carbs today and will be going for first fire.

I am going to run the std fuel pump and just run a "T" with the return (the kind you use for the windscreen washers). A friend of mine used the same thing on his R1 carbed CVH Fiesta and works perfectly.

As for the loom I'm going to leave it in place, i will just disconnect the ECU.

As for the starting problem, I've been searching the forum for the last three hours and found that my problem could lie with the brown multiplug, or a dead starter motor. I've checked both the brown connector and the blue wire going to the starter motor several times and they seemed ok so most likely i have a dead starter motor.

Will be doing a more thorough check with some extra wires and multi-meter this afternoon after i get off work. I really hope i sort it out one way or another because I'd really love to have a first run today.

#5
unariciflocos

unariciflocos
  • Drivers+
  • 706 posts
Joined: 27 Oct 2008
  • Name:Andrei
  • Location:Freiburg, Germany
Garage View Garage
Apparently the starter motor was full of water and it didn't quite like that :(

Engine started as soon as the carb chambers were full with fuel even though I didn't take the time to adjust the dizzy. Fuel was spraying out from every hole, the standard pump is just too much, i got some coolant spraying from the two little holes that go from the head to the std inlet mani, and haven't got to making the vacuum outlet yet. But apart from these little things that need to be sorted out everything is fine and dandy.

If anyone want to see my work:
Posted Image
and first fire

how much power do you think I got using this setup: GSXR 1100 carbs, 11.1 CR, Kent PT23 304 deg, port and polished head, 3 angle valve seats, std bottom end?

Cheers guys

#6
notamondayfan

notamondayfan
  • Drivers
  • 753 posts
Joined: 07 Sep 2004
  • Location:Huddersfield & Wensleydale
you can cut off the injectors wires, i did this on my conversion and its perfectly fine, and makes it a little tidier.
just make sure to insulate the wire ends just incase theres a small chance of shorting something.

#7
MrG

MrG
  • Drivers
  • 1,679 posts
Joined: 23 Dec 2007
  • Location:Soham, Cambridge
have you fitted a pressure regulator? The inj pump will be far to much for the carbs, so get one and fit it asap (or replace the pump with a red top, but do a search as its been covered a few times before)

#8
unariciflocos

unariciflocos
  • Drivers+
  • 706 posts
Joined: 27 Oct 2008
  • Name:Andrei
  • Location:Freiburg, Germany
Garage View Garage
I put the wires i didn't need from the loom in a back, put a cable tie around them and concealed them near the brake drum in case i should need them in the future. There will be no cutting :ph34r:.

I noticed the fuel pressure was too high, fuel was spraying out every hole of the carbs. Will get a pressure regulator today.

Also on the list for today: -making an accumulator for the vacuum, a pipe 40mm in diameter, covered at both ends connected to all 4 intakes.
-drilling the jets 1.6 or 1.7 but may have to go 1.8, will go in incremental steps and see how it runs
-smoothing out the inside of the inlet manifold where the welding was done (good diy job, but needs a little bit of tinkering)
-if I don't get proper results with the dizzy I might install a Megajolt system from a friend.

again,how much power do you think I got using this setup: GSXR 1100 carbs, 11.1 CR, Kent PT23 304 deg, port and polished head, 3 angle valve seats, std bottom end?

Thanks,
Andrei

Edited by unariciflocos, 16 December 2008 - 06:23 AM.


#9
unariciflocos

unariciflocos
  • Drivers+
  • 706 posts
Joined: 27 Oct 2008
  • Name:Andrei
  • Location:Freiburg, Germany
Garage View Garage
I've built the vacuum tank and sorted out the fuel pressure but now it doesn't rev :rolleyes:

I hit the throttle and it goes to 3500 RPM after which it drops, and I have to let the throttle down and hit it again for it to go up again.

I don't know what the problem is. Could I have installed the camshaft wrong? I used the std pulley and set the timing belt on the std markings. Or is it a fueling issue?

Please help guys.

Thanks,
Andrei

#10
projectpug

projectpug
  • Drivers
  • 591 posts
Joined: 05 Jun 2007
  • Location:Wrexham North Wales
Ignition timing and fuel would be my first thoughts. Im pretty sure you need a adjustable vernier cam pulley to time up a pt23 its fairly "wild".
Power when timed correctly and with a good ignition curve and carb jetting i would say between 145-160 ish depends too much on the head a poorly ported/polish head will be worse than stock peugeot.

Edited by projectpug, 16 December 2008 - 09:06 PM.


#11
unariciflocos

unariciflocos
  • Drivers+
  • 706 posts
Joined: 27 Oct 2008
  • Name:Andrei
  • Location:Freiburg, Germany
Garage View Garage

Ignition timing and fuel would be my first thoughts. Im pretty sure you need a adjustable vernier cam pulley to time up a pt23 its fairly "wild".
Power when timed correctly and with a good ignition curve and carb jetting i would say between 145-160 ish depends too much on the head a poorly ported/polish head will be worse than stock peugeot.


Is there a guide to how I should adjust the cam tming? Should I advance the cam? Will be increasing jet size today and fiddling a bit more with the fuel pressure and ingnition timing.

#12
projectpug

projectpug
  • Drivers
  • 591 posts
Joined: 05 Jun 2007
  • Location:Wrexham North Wales
Hi,
I would leave the cam timing for now. Start with the things you mentioned and also check your not getting more than 5psi to the carbs.
If you can make a video and post a link would be helpfull to me and anyone else who can help.

#13
unariciflocos

unariciflocos
  • Drivers+
  • 706 posts
Joined: 27 Oct 2008
  • Name:Andrei
  • Location:Freiburg, Germany
Garage View Garage
Could i get away with using a mechanical fuel pump?

Will do some more work tonight after work.

#14
unariciflocos

unariciflocos
  • Drivers+
  • 706 posts
Joined: 27 Oct 2008
  • Name:Andrei
  • Location:Freiburg, Germany
Garage View Garage
Does anyone know what pressure the std injection electrical fuel pump and the carburetor mechanical fuel pump supply?

#15
welshpug

welshpug
  • Pitcrew+
  • 30,025 posts
Joined: 18 Aug 2006
  • Name:Mei
  • Location:Bridgend
standard injection pump just pumps, the regulator controls the pressure (3 BAR/21 psi) and any excess goes back to the tank via a return.

carbs on a 205 IIRC require a max of around 5psi.

#16
unariciflocos

unariciflocos
  • Drivers+
  • 706 posts
Joined: 27 Oct 2008
  • Name:Andrei
  • Location:Freiburg, Germany
Garage View Garage
Will a standard mechanical fuel pump from a carburetor 205 provide enough flow for my 4 carbs?

#17
MrG

MrG
  • Drivers
  • 1,679 posts
Joined: 23 Dec 2007
  • Location:Soham, Cambridge
why not just get a regulator like wp says. My carbs run spot on at 5psi

#18
unariciflocos

unariciflocos
  • Drivers+
  • 706 posts
Joined: 27 Oct 2008
  • Name:Andrei
  • Location:Freiburg, Germany
Garage View Garage
Well the answer is quite simple, mechanical fuel pump - free, fuel pressure regulator - 80 Euros. Might as well give it a try before I go ahead spending money. I've drilled the thermostat and dizzy housing and put the pump in. Will be testing tonight. I bid on a Megajolt system on ebay but the guy said he won't ship to Romania :unsure: I have 100% positive feedback. Peoples preconceptions are so frustrating sometimes.

Edited by unariciflocos, 19 December 2008 - 09:39 AM.


#19
MrG

MrG
  • Drivers
  • 1,679 posts
Joined: 23 Dec 2007
  • Location:Soham, Cambridge
they are you're right. Good luck on it.

#20
projectpug

projectpug
  • Drivers
  • 591 posts
Joined: 05 Jun 2007
  • Location:Wrexham North Wales
Welshpug is correct 5psi max for carbs any more will damage the carbs and increase the risk of fire. Regarding the 205 carb pump i dont know as the most popular method here is to used a dual regulator set up. I have mine set at 4.5psi and it runs fine. The other way is to install a facet red top . But i suppose there is no harm in fitting the mechanical one and then seeing how you get on.