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RatRod
10-26-2009, 12:38 PM
First of all, thanks for all of the info that made this conversion possible from everyone elses threads. I have installed a Weber 32/38 on my wifes 88 LX. It started and ran great to begin with, but now idles and runs really rough after about a maiden voyage of 20 miles. The Weber guy said to pull the idle jet and check/clean them in case they have junk in them and I will do that tomorrow. My main questions though are about the pcv valve in the intake manifold. I pulled it out and the plastic thing under the manifold has a broken ring at the top keeping it from sealing well. Do I need to keep the pcv routed to the plastic box under the manifold or can I just cap off the vacume coming off of the manifold going into the pcv/plastic box. I tried it, but the plastic box under the manifold was either blowing or sucking air and I'm not sure how to get rid of it if necessary. The second question is in your how to section it said not to remove the thermovalves. What are these and where are they located? I plugged off the AS valve with JB weld also, because of the noise/air leakage. I'm not sure if that caused any problems or not too. Sorry so many questions at once, but once I get it to running I have an original carb and parts for free if anyone wants to pay shipping from Eufaula, OK.
Thanks in advance for any help you may offer :)

RatRod
10-29-2009, 12:56 PM
Could anyone even tell me what and where the thermovalves are ???

greentee76
10-29-2009, 05:06 PM
Welcome...
The pcv valve... I do not have mine routed through the intake manifold as mine broke there as well. I disconnected the hose from bottom of the manifold and routed it through one of the openings. The pcv valve will fit the hose itself just fine. You may need to use a longer hose on the top side of the manifold to make this work. I'm pretty sure I used a piece of hose off one of the white dics shaped valves that I removed on mine.
Thermovalves -- there are two on the drivers side rear of the intake manifold one with two vacuum hoses and one with three. There is also one on the top of the thermostat housing with two vacuum hoses. They are now fancy water plugs.
Hope this helps and good luck.

88Accord-DX
10-29-2009, 05:24 PM
Some things that helped me out with my weber problems was to put in a fuel pressure regulator & in-line fuel filter about a foot from the carb. Also, if that is a used weber, it should be re-built. These carbs need to be tweeked a couple of times to get to run right, there is how to on weber's website.

PCV system needs to work. Covered ^ in previous post w/ thermovalve.

For future reference, you get better gas mileage when you open up the exhaust also.

RatRod
11-23-2009, 09:34 PM
I replaced the timing belt, distributor, wires, plugs and It's still running rough. Tomorrow I'm going to try to talk Weber to take it back and check it out.

A20A1
11-29-2009, 04:05 PM
If you remove the AS valve vacuum hose that operates the valve and the AS valve still leaks then the valve is bad. Good thing you sealed it though.

Best thing to do is remove all vacuum hoses and then build up from there.

If you have problems running the carb it could be from the adapter plates not sealing properly causing a vacuum leak.
Screws inside and out can wiggle free and cause problems. I had my float valve work its way down from the roof of the weber lid and it cut off fuel flow to the float.

The thermovalves (2) at the back of the intake manifold will simply keep coolant that is flowing inside you intake manifold from spilling out when they are not in use. Did you plug the coolant hole in the intake manifold that sits beneath the carburetor base plate?
If you don't see the thermovalves it could be because your car uses different emission standards or they have long since been broken off.

If the carb is new I see no reason to return it to Weber, tuning needs to happen on the car anyways.

I would leave the PCV connected to the motor at the bottom, use an oil safe rubber hose of equivalent diameter to replace the broken one and run it up to the PCV valve then from the valve to an intake manifold vacuum port, front or back.

2oodoor
11-29-2009, 05:12 PM
Something to pay close attention to as well, the studs on the adapter plate can turn as you are tightening the nuts. This can push the plates apart thus causing them to distort and leak vacuum.

Most Webers will run different as the outside temperature changes too. Good thing all I have to do is tweak the idle mix screw with my fingers, taking all of thirty seconds to do an nothing to remove nor any tools needed. ;o)
Getting a good jet kit with some step sizes in between multples of five for the idle jets (52,53,58 etc. as opposed to 50.55.60) helps with that too.