16 replies to this topic

[loiselle.m]

Hey everyone!

My 87 RT4WD had been over heating for a little while, and I kept having to add coolant. So we did the head gasket, and since we were going to have the head and the manifolds off, my dad and I decided we might as well swap carbs to the Weber 32/36 instead of having to re-assemble the stock carb in all its vacuum glory. The over heating seemed to have been taken care of, but then it started climbing again (just past 3/4 of the gauge) after a 500km trip...added coolant this morning and it's been fine all day for city driving. Other than that both the lower and upper rad hoses are new and so is the rad - so I am waiting for my thermostat to come in and I will see if that will solve the issue.

Anyways that's a whole other issue - on to the carb problem. The engine is stock, but we gutted the cat before putting it back on. We also modified the stock air breather to fit the Weber, and tried to route vacuum to keep the the air coming from the exhaust shield into the intake when the engine is cold - using one of the ?thermo switches? on the intake manifold (but that doesn't seem to be working).
Right now, the issue seems to be a lack of power at higher rpm. The vacuum advance is connected (on the lower vacuum port - as per many threads) and the timing is lined up on the red mark. It idles great, but it doesn't climb up in the rpms like it used to. I will get to highway speeds and it stay there all right, but it feels like it has less power than before. We double checked all the vacuum and everything else we could think of and still nothing. I am not sure what the size of the jets are in the K726 kit, but we were thinking that it was maybe lacking fuel at higher rpm, so maybe a larger jet would be needed. We haven't checked the fuel pressure, fuel pump, and haven't changed the rear fuel filter, because everything worked great with the stock carb...

It's drive-able at least, so I can use it to go to work.

Any help is appreciated!

Mat

A few pics of the swap...
http://www.facebook....=1&l=c1d6456da0

Edited by loiselle.m, 08 November 2012 - 10:11 PM.

[rollz87civic]

Sounds like jetting could be wrong. How good is the accel pump?

[loiselle.m]

The accel pump is good.

[chedda_j]

Did you just throw a carb on there or did you actually tune it.

[loiselle.m]

Well we just threw it on there - I was under the impression that the K726 kit already had the carb tuned properly.

[bigboi407]

no thats not the case, the weber k726 needs to be tuned per engine. Milage, wear, mods and what not will cause the tuning to be different to every engine its applied to, its a great carb once its tuned correctly

[loiselle.m]

Tuning as in adjusting the air/fuel mixture screw?

[chedda_j]

As in you need the proper jets and metering rods. See the tutorial in the carb section.

[rallyxcrx]

You will need the biggest accelerator pump jet, and slightly richer jets, you can get all these from Pierce Manifolds. Make sure you are getting full throttle, or your secondary won't work, Dave

[loiselle.m]

Thanks for all the suggestions! I know for sure I am getting full throttle, it's an issue we already worked out. Anyone know what the jets in the K726 kit are? I'm away from home so I can't take it apart, but I'd like to order some richer one's before I get back...

[chedda_j]

Order the ones in the weber how to.

[Mark L]

As in you need the proper jets and metering rods. See the tutorial in the carb section.

Small point, Webers do not have metering rods.

[chedda_j]

Thanks. I have never had to tune mine. I tuned allot of edelbrocks. My weber that was on the crx was previously tuned. So if no rods, then how does it regulate fuel flow through the jets?

[loiselle.m]

Ordered a few different size jets for the secondary main and the secondary air correction from Pierce Manifolds. Will post updates to see what works best.

[loiselle.m]

Didn't forget to update...haven't had the chance to swap the jets out yet. Should have time before the new year