When I first started working on my car, I was taking off the cross over pipe. In doing so I had to remove the pressure chamber that is mounted on top of it. When I went to move it out of the way, I heard a pop...... It was an old check valve that split in half. I ordered some new ones from Dale Clark. Finally got around to installing them today.

I replaced the one I broke with no problem, the one going from the Pressure tank to the Y-pipe. I replaced the one for the (I think) charge control with no problems. When I was replacing the one for what I believe to be the double throttle control....I broke the nipple of the solenoid valve....... Please advise me otherwise if I mixed up these lines.

Does this mean I have to remove the UIM and pretty much all of the rats nest to replace this?

Is now a good time to get 30+ feet of viton hose and get to work?

Or if this is the double throttle solenoid, will I be ok not fixing it until later. So long as I make sure the motor is warmed up before boosting?

The broken solenoid is along the bottom row, furthest toward the front of the car, under the UIM. Here are some pics of what broke. I drew in the check valve and rubber line in white. I think the rest is pretty much self explanatory, well that probably is too but what the hell.....

 

Hard to tell from the pics what all you need to do. If the broken solenoid is just for the double throttle, I wouldn't worry about it too much until you're in there next time with the UIM off. Most of the solenoids can be removed from the rack and replaced without having to dig the whole rack out.

I always recommend just replacing the hoses that you frequently have to remove to service the car, like the ones to the UIM and MAP sensor with silicone hose. And, of course, replace the hoses with the check valves in them. There's really no good need to do ALL of the hoses - the ones that connect a solenoid to the rack are baked on there and are working fine - just leave them be.

BTW, I recommend quality silicone hose over Viton - I use HoseTechniques.com stuff, fits great and is reasonably priced. Viton is nice, but it's a little harder to work with and much more expensive without any real benefit. *Quality* silicone hose will stand up to oils no problem - I've been using HT stuff for about 10 years and have NEVER had a failure. That said, for the lines going to my oil catch can I used Viton - lines that will see a LOT of oil, you're better off using proper Viton tubing.

Dale

 

Are the solenoids shown in the stock diagram in order? If they are, then it is the double throttle solenoid that broke. Last one on the bottom towards the front of the car.

https://www.rx7club.com/showthread.p...vacuum+diagram

Will I need to plug the line that broke?

 

Well I got it all back together without plugging the broken lines. It makes a hell of a whistle when it starts up cold but goes away shortly. I have been making sure to warm it up very well before I start boosting too. Other than that she is running great!!