help me please
09-07-10, 10:51 PM
#32
I need a new user title
Join Date: Oct 2005
Location: Yaizu, Japan
Posts: 2,646
Likes: 0
Received 0 Likes
on
0 Posts
09-08-10, 11:46 AM
#33
Full Member
Thread Starter
Join Date: Jul 2010
Location: mo
Posts: 57
Likes: 0
Received 0 Likes
on
0 Posts
the idl is fine i got it to idle it is still bogn when it is at an idle an u try to idle it up real fast idle is real smooth now it was the float that was messn with the idle
09-08-10, 12:04 PM
#34
I need a new user title
Join Date: Oct 2005
Location: Yaizu, Japan
Posts: 2,646
Likes: 0
Received 0 Likes
on
0 Posts
Ignore the problem with quick changes in throttle position for now; that's the accelerator pump circuit and you don't mess with that until the end because it's greatly affected by the idle circuit. Is cruising smooth? Is slow, low-load acceleration smooth with no flat spots?
09-08-10, 03:06 PM
#35
Full Member
Thread Starter
Join Date: Jul 2010
Location: mo
Posts: 57
Likes: 0
Received 0 Likes
on
0 Posts
no it is not crusing smooth an when u idle it up slow if gose up fine till it hits 3 k an then starts to spuder like it is missing but its not missing an it will cruse good till it hits 3k or right befor an the higher u go up the worse it gets idk. man i wish there was some one round here that knows bout these carbs that i could take it to :{
09-08-10, 03:41 PM
#36
I need a new user title
Join Date: Oct 2005
Location: Yaizu, Japan
Posts: 2,646
Likes: 0
Received 0 Likes
on
0 Posts
That's what I thought. Try 55F9 idle jets to start with. If it gets better but it's still not entirely smooth, decrease the idle jets by 5 until it is. You will have to adjust the idle each time you change idle jets. If cruise is smooth after that but you still experience a stumble at around 3000 RPM, you'll have to play with main jets and emulsion tubes.
As for the accelerator pump jets, you can get a hint of what you need by seeing whether it gets better or worse when you go down in idle jet sizes. If it gets worse, you probably need bigger AP jets. If it gets better, you need smaller AP jets. The AP jets you have are already pretty big, so if you end up needing bigger than 70 jets (the largest you can buy from Weber AFAIK), try using a blank AP bypass jet to maximize the AP shot.
Yes, this is all trial and error, especially since you don't have an air-fuel ratio gauge. You're going to end up buying a lot of jets before you get your tune right. This is why fuel injection is awesome.
As for the accelerator pump jets, you can get a hint of what you need by seeing whether it gets better or worse when you go down in idle jet sizes. If it gets worse, you probably need bigger AP jets. If it gets better, you need smaller AP jets. The AP jets you have are already pretty big, so if you end up needing bigger than 70 jets (the largest you can buy from Weber AFAIK), try using a blank AP bypass jet to maximize the AP shot.
Yes, this is all trial and error, especially since you don't have an air-fuel ratio gauge. You're going to end up buying a lot of jets before you get your tune right. This is why fuel injection is awesome.
09-08-10, 04:52 PM
#38
I need a new user title
Join Date: Oct 2005
Location: Yaizu, Japan
Posts: 2,646
Likes: 0
Received 0 Likes
on
0 Posts
Rotary jetting requirements are a bit different from piston engine jetting requirements, so you're probably not going to find a kit with the range of jets you need.
Here's where I usually buy my Weber jets:
http://www.webercarbsdirect.com/default.asp
Here's where I usually buy my Weber jets:
http://www.webercarbsdirect.com/default.asp
09-09-10, 01:48 PM
#39
Full Member
Thread Starter
Join Date: Jul 2010
Location: mo
Posts: 57
Likes: 0
Received 0 Likes
on
0 Posts
http://www.mazspeed.com/carburetorfacts.htm
hey guys go to this site an bout thrid paragrap down this guy says that with the weber 45mm dcoe on a 12a that u can never get rid of the bog they have when u floor it he says the lowest rpm u can floor it is bout 3k an thats where i have to put mine to floor it so is he right
hey guys go to this site an bout thrid paragrap down this guy says that with the weber 45mm dcoe on a 12a that u can never get rid of the bog they have when u floor it he says the lowest rpm u can floor it is bout 3k an thats where i have to put mine to floor it so is he right
09-09-10, 02:56 PM
#40
I need a new user title
Join Date: Oct 2005
Location: Yaizu, Japan
Posts: 2,646
Likes: 0
Received 0 Likes
on
0 Posts
It's true that the bog won't ever fully go away. That's the disadvantage of a big, non-progressive carb. However, it can be reduced with tuning. The stumble from opening the throttle quickly, on the other hand, can be almost completely eliminated, even with 40mm main venturis like mine. You might end up with a bit of a miss if you floor it from idle, but it shouldn't be noticeable while you're driving.
Actually, I take that back. You can eliminate the bog. It just requires a little help from a turbo.
Actually, I take that back. You can eliminate the bog. It just requires a little help from a turbo.
09-09-10, 11:15 PM
#43
Full Member
Thread Starter
Join Date: Jul 2010
Location: mo
Posts: 57
Likes: 0
Received 0 Likes
on
0 Posts
its a crapy one puts out 30gph ok but i got some up dates was workn on it to day it idles fine not no crazy rpm bounce. but when it sits for a min it starts to idle messed up k an if u rev it up a bit it gose back fine but i have my floats set at 12.7mm k an now it cruses fine till u get to 3k in any gear nless u r geting on it so when i go up in 5th an hit 60 it starts to spuder an the fule pump is a mr.gasket one i used when i rebuilt my nicki so what u think an could that b y it spuders when it 3k to an 3k is where the main jets kick n right.let me know what u all think
09-11-10, 05:16 PM
#45
I need a new user title
Join Date: Oct 2005
Location: Yaizu, Japan
Posts: 2,646
Likes: 0
Received 0 Likes
on
0 Posts
Seriously, dude, I can barely read your posts. Please, for the love of God, proofread them just a little before you submit them.
That fuel pump isn't great, but that isn't your problem. I'm more concerned about your fuel pressure regulator. The Mr. Gasket style ones are known to be of pretty terrible quality. If it's not putting out a consistent pressure, that will make diagnosing problems very difficult. Do you have a decent fuel pressure gauge, at least? If so, what does it say?
For the idling issue: use a flashlight and look down the carb while it's having its problem. Tell me if you see any dripping. You may need to use a mirror.
What exactly did you do to make it cruise smoothly at low speeds? Does it cruise smoothly again once you're above 3,000 RPM?
Do me a favor and pull your leading spark plugs and post a close-up picture of them. You can tell a lot about generally what AFRs the engine is seeing by looking at their color.
That fuel pump isn't great, but that isn't your problem. I'm more concerned about your fuel pressure regulator. The Mr. Gasket style ones are known to be of pretty terrible quality. If it's not putting out a consistent pressure, that will make diagnosing problems very difficult. Do you have a decent fuel pressure gauge, at least? If so, what does it say?
For the idling issue: use a flashlight and look down the carb while it's having its problem. Tell me if you see any dripping. You may need to use a mirror.
What exactly did you do to make it cruise smoothly at low speeds? Does it cruise smoothly again once you're above 3,000 RPM?
Do me a favor and pull your leading spark plugs and post a close-up picture of them. You can tell a lot about generally what AFRs the engine is seeing by looking at their color.
09-11-10, 10:35 PM
#46
Full Member
Thread Starter
Join Date: Jul 2010
Location: mo
Posts: 57
Likes: 0
Received 0 Likes
on
0 Posts
ok sorry man, i have a ok fuel pressure gauge, when u rev it up it bounces from 3 too 2 psi but at a ldle it looks to b fine but i will know more when i get the better fuel pump regulaor. The one i got coming has a gauge biult on it, it is from rspec i gave like 35 for it. An it has a return line on it to. But as for the dripping i will look tomarrow as it is dark now. An as for the cruise i just reset the foats to 12.7mm. but no it dose not cruise, after u get to 3,000rpm it gose ok for a few seconds then it will spudder then go good for a few more seconds an it keeps doind this the faster you go. an i will get the pics up of the spark plugs. an once more i am sorry bout the bad typen. i just get n a hurry.hope to here back really need the help
09-12-10, 08:41 AM
#47
Waffles - hmmm good
iTrader: (1)
ok sorry man, i have a ok fuel pressure gauge, when u rev it up it bounces from 3 too 2 psi but at a ldle it looks to b fine but i will know more when i get the better fuel pump regulaor. The one i got coming has a gauge biult on it, it is from rspec i gave like 35 for it. An it has a return line on it to. But as for the dripping i will look tomarrow as it is dark now. An as for the cruise i just reset the foats to 12.7mm. but no it dose not cruise, after u get to 3,000rpm it gose ok for a few seconds then it will spudder then go good for a few more seconds an it keeps doind this the faster you go. an i will get the pics up of the spark plugs. an once more i am sorry bout the bad typen. i just get n a hurry.hope to here back really need the help
This is probably being caused by the regulator shunting the flow and your weak
pump which can't keep the pressure up during the cruising speed. Get rid of the
regulator and see how it does. Should act better and it sound likes its not
powerful enough to overrun the carb anyway.
You can't tune the carb until your fuel delivery issue is addressed. You have an obvious
fuel pressure/flow problem and until its fixed it will never run correctly. And whoever
said it will always bog and you can't floor it until 3k is full of BS and doesn't know how
to tune a carb. My Dell (which is webber knockoff) idles fine and does have a very slight
bog but I can floor it off idle if I want want and it will not buck, spudder or die. It will
emit a big bellow until it starts singing around 2.5K but that's a lovely sound to me
I told you to get rid of the Mr. Gasket thing in post 8, and now its 40+ posts later
and you still have it hooked up
Oh yeah and try to communicate in english, not textese.
09-12-10, 02:28 PM
#49
I need a new user title
Join Date: Oct 2005
Location: Yaizu, Japan
Posts: 2,646
Likes: 0
Received 0 Likes
on
0 Posts
Yes, it would. Don't take the regulator off. Just get a decent one instead. If you had a stock pump you could run it without a regulator, but the stock pump is terrible anyway.