Carbeurator guys... Car won't run cold.

[notfred]

I've got an 86 Honda CRX w/ a 3bl carb on it. The car won't run unless it's warm. I think it's a carb issue, but I don't know a lot about carbeurated cars (All my cars have always been FI). How hard would it be to rebuild the carb, and do you even think it's neccessary?

 

[notfred]

P.S. don't reply unless you've actually rebuilt a carbeurator before.

 

[Zim Hosein]

Rebuilding a carb isn't hard. I had a 4B Carb on my old Camaro, all it takes it some invested time and patience

 

[notfred]

How much time are we talking about?

 

[Nohr]

I haven't rebuilt any carburetors, but I did stay in a Holiday Inn Express last night.....

 

[cornbread]

I rebuilt a carb on a lawnmower before

 

[thedarkwolf]

Make sure the choke is closed when its cold before you go and rebuild it. Without the choke it would be a pain to get it started.

 

[ViperXX]

Yes, there is a little do hickey that you adjust the choke with. As the car warms up the choke opens up. If you have the choke opened to far when it's cold it won't start.

 

[tcsenter]

How much time are we talking about?

It took me about eight hours to rebuild a 2-bbl Rochester carb from a 1978 Buick Regal (231c.i.), but then I'm a bit meticulous. I completely disassembled it, cleaned every spring and screw with parts solvent, etc. Suffice to say, it requires a bit more to rebuild pollution controlled carbs than it is to rebuild a non-emissions Holley 750.

I got a book on general carb rebuilding that I bought from an auto parts store, I recommend you do the same. The premium rebuild kit was made by Standard, which is a pretty good brand.

Does it have an electric choke? It may be the choke, or the butterfly valve which shunts warm air from the manifold into the air filter housing during cold weather, either being more simple to repair.

 

[AlienCraft]

Not a job for a first timer..... UNLEss you're willing to READ THE F^&(inG MANUAL !!! FIRST!!!
Really ... go get a GUARANTEED Rebuilt from PepBoys or AutoZone <uncompensated commercial endorsment... Much easier on the whole and you won't have the issue of "spare parts leftover" or warped/ torn gaskets.... I've done quite a few and I've decided we'll let the guy's rebuild and test 'em , I'll install them... Boats, bikes, cars all the same to me.,....

 

[Eli]

I highly doubt you need to rebuild the whole carb. If it runs fine when it's warm, then it's most likely a choke problem.

I suggest you get the Chilton or Haynes manual for your car, and check into the choke settings...

Do you have a chainsaw? Try and start it without using the choke.

Btw, It's carburetor.

 

[Bluefront]

Late model jap carbs can be very difficult. Some are electronic controled, such as my 86 Nissan PU. They are not meant to be dumped in carb cleaner. They have many small parts....some of the jets can be mixed up. You may have extreme difficulty removing some jets due to varnish build-up.

I'm not certain about the cold-start system on your carb....some don't have a choke at all. They use a cold start jet system, controlled by an electronic control unit (ecu). It certainly does sound like this is your problem. It may not require a complete overhaul. My nissan carb takes about three hours or so to rebuild. A first-timer will have a bunch of trouble.....

 

YGPM

 

[snooker]

I would lean towards a choke issue also.

Runs good warm but not cold then the choke is not closing when it is cold, thus getting way too much air into the air/fuel mixture for a cold engine (Hence the name choke )


Rebuilding is easy and hard. It is easy because it is like taking a 3d puzzle apart and putting it back together, but hard because of the sizes of alot of the parts that go into rebuilding carbs.

 

[Scarpozzi]

Once again, the choke sounds like the prob. It's actually called the "automatic choke". It's supposed to be closed to start with and then open up when the car starts. What I would suggest doing is pressing the gas pedal once before you start the car and then let up on it. On older model cars that would set the automatic choke accordingly and it would start. If all else fails, keep a $2 bottle of Ether in your glovebox and squirt some in your carb when you're in a rush to get it fired up...just don't use too much.

I would also suggest possibly getting some carb cleaner. That's also a bottle you can buy. It will keep the parts greased and possibly fix this problem altogether. You should be able to rebuild a carb in a few hours....they're not even hard to remove since they're on top of the engine. Take it from a TN boy though.........don't rebuild it until you find out WHY you need to rebuild it.

 

[SuperSix]

It's something simple, something with the choke, I doubt it needs rebuilt.

I wouldn't touch a jap carb with a ten-foot pole.. I would run to an auto parts store and get a rebuilt one if it needed it.

<-- rebuilt a 4Bbl Rochester computer-controlled carb..

 

[Iron Woode]

My friend and I rebuilt a 2bbl for a Hyundi (sp?) Pony. It was pretty simple, but there was a lot of small parts. A complete rebuild kit is a good idea. Can be quite expensive.

It maybe the choke, but since its that old, why not just rebuild. Or buy a rebuilt carb. At least you will have a warranty if it screws up.

 

[HomeBrewerDude]

yeah, its probably just the automatic choke mechanism. I rebuilt a 4 barrel many many years ago.. it was a pain in the ass.

 

[monckywrench]

You can easily isolate wether it is the choke, IMO the most likely problem.
Begin with engine cold.
Remove air cleaner/cover and look into the top of the carb.
Note position of the top "butterfly" plate. Is it mostly open?
Have a helper hold the plate closed. Start engine and observe behavior. If it runs better with plate held closed the choke is most likely cause.
Refer to electric choke troubleshooting in manual. Make sure it gets power to the resistance heater if it uses one. Check for disconnected wires and vacuum lines. Vacuum leaks can mimic choke problems.
The usual safety precautions apply such as keep body parts away from spinning pulleys and have a fire extinguisher available when working with fuel systems.
If you elect to rebuild, do not rebuild your present carb because if it has problems you will not be able to drive your car.
Instead, get an IDENTICAL carb from a junkyard and rebuild that.
_Check rebuild kit prices first and compare them to remanufactured carbs!_
Spray carb cleaner is not suitable for deep cleaning, just for pre-cleaning (gettin the major crud off) and post-dip touch-up.
Get a small tub of Gunk Hydro-Seal cleaner instead. It lasts a long time and can be used for cleaning other metal parts.
Wear gloves and rinse off parts with hot water after cleaning, then dry with spray carb cleaner or compressed air.
Rubber-tipped blow guns rule for this.
If you have a digital camera use it during teardown. They are superb for keeping track of auto work and you can burn the pics to CD for future use.

 

[Brutuskend]

I've rebuilt MANY carbs. and it's not that tough.

However, from what you discribe it sounds like the carb may just have a vac. leak. (When the engine warms up everything expands, sealing the leak)

To check this. Get a can of ether or carb cleaner and spray it around the base of the carb, and the body of the carb while the engine is still cold. It the RPM's go up....you have a leak.

 

[notfred]

the engine won't idle at at while it's cold. it'll jsut die if you take your foot off the gas before it's warmed up. The car has 188k miles on it, so jsut about anything could have worn out by now.

 

[Brutuskend]

Yup, sounds like a Vac leak to me...

Tighten all the screws on the carb you can reach (the one's holding it togather). Tighten the nuts @ the base holding it on the engine.

 

[Quixfire]

I have experince with the Kien 3bbl carb Honda used on these engines. First, even if you have rebuilt a carbeurator before these carbs are complicated, they require some special tools to set idle, mixture and float level correctly.

Secondly, sounds like a choke problem, may not be shutting when the throttle is depress prior to starting.

I do recommend taking it to a honda mechanic for this repair.