Carburetor - buy or repair?

[duskylim]

hi dusky,
thanks for your comments, i might have to use the 5k for now as i have to save for another carb... btw, would you know how much a 3k carb would cost? whether surplus or brand new... i noticed though my 5k carb is much simpler than the 2e carb, some components were not connected to the 5k carb, the actuator is actually not used anymore...

Dear dod:

Matagal na ako di bumibili ng carburador. I really can't say what the price is now, I do know that the newer carbs use a lot of plastic components, which tends to make them more susceptible to cracking and breakage.

If you're happy with the 5k then by all means keep on using it.

If you're looking for carbs try calle Antipolo in Tondo, or Giant in Banawe they usually have carbs set aside for sale.

If you go to Giant, first ask for the price at the front desk - you can haggle and ultimately you will find the base price - that's what you will pay regardless for a good or bad part.

Then, hang around until the mechanics go on break.

Talk to them and get to know them. Bumili ka ng merienda for them.

If you find someone you can work with come to an off-the-table agreement (maybe Php 200 to 500 depending on the carbs you want) and have them pick or set up a nice carb for you.

A little kindness goes a long way. Share the love.

That way you will get the best parts they have been hoarding just for customers who understand how to make an 'inside' deal.

That's how I used to do it.

Regards,

Dusky Lim

[duskylim]

sorry double post

[dod]

Sir Dusky,
thanks for all your input... appreciate it very much...

[duskylim]

Dear dod:

You're very welcome, always glad to help.

Regards,

Dusky Lim

[djmhoi]

Guys! if your planning to buy a brand new carb (4K that is) here's a link http://cgi.ebay.ph/Toyota-4K-Carburetor-Assembly-Brand-New-/280520042285?cmd=ViewItem&pt=LH_DefaultDomain_211& hash=item41504c272d

here's the seller http://myworld.ebay.ph/zalexautoparts/

2 years ago i was planning to get this carb from this seller as well for my mistubishi 1300cc cyclone engine because my mikuni carb drink's a lot of gas (3-4 km/l city driving - 7-8 km/l highway) and performs bad on climbs, but then i found another stock carb (piston type venturi) for my engine. i think you'll gonna need an adaptor for it to fit on mitsu engines.

actually i have my carb done on m2m kamuning 2 months ago for the 2nd time... and the works are not good this time... the first time was good 2 yrs ago... and it's it performs well for 2 yrs until they have opened it again 2 months ago... since then... it lacks power, need to heat the engine before you can drive it, because it's gonna jerk all the time... b4 you just start the engine and go...

i'm gonna try a&m this month... gonna post some feedback then...

hope this helps

[duskylim]

Guys! if your planning to buy a brand new carb (4K that is) here's a link http://cgi.ebay.ph/Toyota-4K-Carburetor-Assembly-Brand-New-/280520042285?cmd=ViewItem&pt=LH_DefaultDomain_211& hash=item41504c272d

here's the seller http://myworld.ebay.ph/zalexautoparts/

2 years ago i was planning to get this carb from this seller as well for my mistubishi 1300cc cyclone engine because my mikuni carb drink's a lot of gas (3-4 km/l city driving - 7-8 km/l highway) and performs bad on climbs, but then i found another stock carb (piston type venturi) for my engine. i think you'll gonna need an adaptor for it to fit on mitsu engines.

actually i have my carb done on m2m kamuning 2 months ago for the 2nd time... and the works are not good this time... the first time was good 2 yrs ago... and it's it performs well for 2 yrs until they have opened it again 2 months ago... since then... it lacks power, need to heat the engine before you can drive it, because it's gonna jerk all the time... b4 you just start the engine and go...

i'm gonna try a&m this month... gonna post some feedback then...

hope this helps

Dear Sir:

I'm very surprised by your comment that a Mikuni carb has worse fuel economy vs an Aisan.

Having grown up with and tuned both carbs I can definitely say the Mikuni when properly tuned will give better economy - both city and highway driving.

The Aisan will give you more top-end, full-bore power - for several reasons.

1) The Mikuni uses a 21 mm primary main venturi with a 28 mm primary throttle plate. The Aisan has a 23 mm primary main venturi and a 28 mm primary throttle plate.

2) the Mikuni uses a 27 mm secondary main venturi with a 32 mm secondary throttle plate, the Aisan has a 28 mm secondary main venturi and a 32 mm secondary throttle plate.

So as you can see from airflow alone the Aisan will outflow the Mikuni.

However, due to the smaller venturi throats, the Mikuni will produce a stronger suction signal and faster airflow - which results in better response and fuel atomization both of which mean better fuel economy.

This is particularly important in the primary system - because you drive on this system 80 to 90 percent of the time - you really only use the secondary for a long time at highway speeds.

3) the Aisan has a triple secondary venturi while the Mikuni has only a double secondary venturi - so even with the larger airflow the Aisan secondary should still produce a good suction signal and atomization.

4) the Mikuni's emulsion tubes are long and thin, occupying little space in the emulsion well, meaning they are RICH TUBES.

The Aisan's emulsion tubes are short and fat, occupying a lot of space in the emulsion well - meaning that they are LEAN TUBES.

However, the Mikuni emulsion tubes have air holes all along their length, greatly weakening the suction signal - leaning them out.

The Aisan's emulsion tubes have holes only at the very bottom (to let gas in) and very small ones at the top (to let air in), - this design mimics a rich tubes behavior.

5) the Aisan's secondary throttle is actuated by a mechanical linkage and opens full when floored - while the Mikuni's secondary is vacuum-actuated.

I have much experience tuning both on our Galant Sigma and my friend's Lancer GSR.

I in fact had twin downdraft Mikuni's and Weber 32/36 DGAV's.

The Mikuni carb is closer to the Weber in the idle circuit, throttle plate and accelerator pump design.

The Aisan (3K, 4K, 5K) carb is quite different.

Best Regards,

Dusky Lim

[djmhoi]

Dear Sir:

I'm very surprised by your comment that a Mikuni carb has worse fuel economy vs an Aisan.

Having grown up with and tuned both carbs I can definitely say the Mikuni when properly tuned will give better economy - both city and highway driving.

The Aisan will give you more top-end, full-bore power - for several reasons.

1) The Mikuni uses a 21 mm primary main venturi with a 28 mm primary throttle plate. The Aisan has a 23 mm primary main venturi and a 28 mm primary throttle plate.

2) the Mikuni uses a 27 mm secondary main venturi with a 32 mm secondary throttle plate, the Aisan has a 28 mm secondary main venturi and a 32 mm secondary throttle plate.

So as you can see from airflow alone the Aisan will outflow the Mikuni.

However, due to the smaller venturi throats, the Mikuni will produce a stronger suction signal and faster airflow - which results in better response and fuel atomization both of which mean better fuel economy.

This is particularly important in the primary system - because you drive on this system 80 to 90 percent of the time - you really only use the secondary for a long time at highway speeds.

3) the Aisan has a triple secondary venturi while the Mikuni has only a double secondary venturi - so even with the larger airflow the Aisan secondary should still produce a good suction signal and atomization.

4) the Mikuni's emulsion tubes are long and thin, occupying little space in the emulsion well, meaning they are RICH TUBES.

The Aisan's emulsion tubes are short and fat, occupying a lot of space in the emulsion well - meaning that they are LEAN TUBES.

However, the Mikuni emulsion tubes have air holes all along their length, greatly weakening the suction signal - leaning them out.

The Aisan's emulsion tubes have holes only at the very bottom (to let gas in) and very small ones at the top (to let air in), - this design mimics a rich tubes behavior.

5) the Aisan's secondary throttle is actuated by a mechanical linkage and opens full when floored - while the Mikuni's secondary is vacuum-actuated.

I have much experience tuning both on our Galant Sigma and my friend's Lancer GSR.

I in fact had twin downdraft Mikuni's and Weber 32/36 DGAV's.

The Mikuni carb is closer to the Weber in the idle circuit, throttle plate and accelerator pump design.

The Aisan (3K, 4K, 5K) carb is quite different.

Best Regards,

Dusky Lim

Sir,

I know for a fact that Mikuni is a very good carb. when i acquired my car 3 yrs ago, the mikuni carb was installed on it... i would say it's a good carb for flat roads before but when we went to tagaytay using the sta. rosa laguna route, there's an steep uphill road somewhere in silang... we almost didn't make it to the top...

i brought it to a&m kamuning to have a work on it... and they did... it became more responsive and powerful enough... and i would say it can now climbs steep roads no problem... but sad to say it's still not fuel efficient...

that's the time i made a decision to replace it with the stock carb installed on cyclone engine (piston type)... and i would say i made the right decision because it's packed with power and economy (7-8km/l city driving, 13-15km/l highway) compare to my previous mikuni carb (3-4km/l city drive, 7-8km/l highway)... we drove the car to baguio 3x, no problem...

i still have the mikuni carb and monifold right now, the mechanic at m2m who who installed the piston type carb 2 yrs ago said that the mikuni carb installed on my car before is not compatible with my engine... it's should have been installed on a 2.0 up engine... i have to believe that because it looks bulky... i don't know really.

i hope you don't mind sir, where can i find the repair kit for carb (piston type)... i'm planning to buy one and take the car to kamuning to have a look at the carb again... 'cause 2 months ago m2m didn't make a good work on it... i'm gonna try a&m this time...

thanks for the inputs sir...

[duskylim]

Dear Sir:

When you say 'piston type' do you mean:

a) a fixed-venturi carburetor that has a 'piston type' accelerator pump - like the Aisan series

or

b) a variable-venturi carburetor like the SU-series or Stromberg series that has a dashpot piston controlling the airflow?

Those are two entirely different carbs.

I will assume it is the former type of carb - then go to Banawe st, and look for any long-established Toyota dealer (Denso, MR2 etc).

They are sure to have good quality repair kits.

Make sure you give them the CORRECT model of carb as there are a lot of variations.

Regards,

Dusky Lim

[djmhoi]

Dear Sir:

I'm very surprised by your comment that a Mikuni carb has worse fuel economy vs an Aisan.

Having grown up with and tuned both carbs I can definitely say the Mikuni when properly tuned will give better economy - both city and highway driving.

The Aisan will give you more top-end, full-bore power - for several reasons.

1) The Mikuni uses a 21 mm primary main venturi with a 28 mm primary throttle plate. The Aisan has a 23 mm primary main venturi and a 28 mm primary throttle plate.

2) the Mikuni uses a 27 mm secondary main venturi with a 32 mm secondary throttle plate, the Aisan has a 28 mm secondary main venturi and a 32 mm secondary throttle plate.

So as you can see from airflow alone the Aisan will outflow the Mikuni.

However, due to the smaller venturi throats, the Mikuni will produce a stronger suction signal and faster airflow - which results in better response and fuel atomization both of which mean better fuel economy.

This is particularly important in the primary system - because you drive on this system 80 to 90 percent of the time - you really only use the secondary for a long time at highway speeds.

3) the Aisan has a triple secondary venturi while the Mikuni has only a double secondary venturi - so even with the larger airflow the Aisan secondary should still produce a good suction signal and atomization.

4) the Mikuni's emulsion tubes are long and thin, occupying little space in the emulsion well, meaning they are RICH TUBES.

The Aisan's emulsion tubes are short and fat, occupying a lot of space in the emulsion well - meaning that they are LEAN TUBES.

However, the Mikuni emulsion tubes have air holes all along their length, greatly weakening the suction signal - leaning them out.

The Aisan's emulsion tubes have holes only at the very bottom (to let gas in) and very small ones at the top (to let air in), - this design mimics a rich tubes behavior.

5) the Aisan's secondary throttle is actuated by a mechanical linkage and opens full when floored - while the Mikuni's secondary is vacuum-actuated.

I have much experience tuning both on our Galant Sigma and my friend's Lancer GSR.

I in fact had twin downdraft Mikuni's and Weber 32/36 DGAV's.

The Mikuni carb is closer to the Weber in the idle circuit, throttle plate and accelerator pump design.

The Aisan (3K, 4K, 5K) carb is quite different.

Best Regards,

Dusky Lim

Dear Sir:

When you say 'piston type' do you mean:

a) a fixed-venturi carburetor that has a 'piston type' accelerator pump - like the Aisan series

or

b) a variable-venturi carburetor like the SU-series or Stromberg series that has a dashpot piston controlling the airflow?

Those are two entirely different carbs.

I will assume it is the former type of carb - then go to Banawe st, and look for any long-established Toyota dealer (Denso, MR2 etc).

They are sure to have good quality repair kits.

Make sure you give them the CORRECT model of carb as there are a lot of variations.

Regards,

Dusky Lim

sir

i think its:

a) a fixed-venturi carburetor that has a 'piston type' accelerator pump - like the Aisan series

it's the common carb for mitsu lancers late 80's until the pizza type 1300 and 1500 cyclone engines, i think...

i checked my mikuni carb this morning it's really big and it's now corroded and rusty... it's been stocked along time now... i should have sold it before...

regards

[dannybe]

Dear dannybe:

I'm sorry but AFAIK there are little or no spare parts for Solex carbs, that's one of the reasons I recommend using Webers - you can still order parts for them.

Regarding Webers, FCC that is, Filipinas Chemical Corp (aka - the Funny Candy Co) used to carry all the parts.

As to Solex side drafts, try an online search for parts, and good luck. IIRC TRD (Toyota Racing development carried their parts).

BTW how were these carbs stored? Did you DRAIN the GAS from them before keeping them?

That's VERY IMPORTANT, if you did NOT do this, it's quite likely that the gas has evaporated and left a hard white crust that will block all the critical passages and DESTROY your carbs.

Open up the top and take a look at the float chamber - it its a mess in there - the carbs are pretty much gone - sorry.

Regards,

Dusky Lim

Hi Dusky,

I opened up the carbs and the inside looks clean. Float is still in one piece.
I bought the solex 40PPH repair kits from wolfscreekracing and am now looking for a carb rebuilder who can do a good job on the mikunis.

How do i clean the exterior of the carbs to make them look spanking brand new?

thanks for all the inputs.