TheSamba.com :: View topic - Rebuilding wbxer questions -attn tencent

Sun May 11, 2008 7:55 pm

Yeah, I'm jazzed that the Syncro I'm picking up had its done a couple years ago. That's most of the asking price right there.

Trans is so easy to drop you can deal with that separately, anyway.

Sun May 11, 2008 8:00 pm

That slight springing back is normal. It happens even with stock studs. It seems the friction of the threads is slightly more than the friction of the washer surface of the nuts (with yellow goo on them) and occasionally the stud will twist slightly.
To help prevent this I run a bottoming tapp in all the nuts and run a die over all the studs to get any sealent off.
I also put a tiny amount of moly lube on the threads making sure not to get any on the washer sealing surface and test run all the nuts.

Sun May 11, 2008 8:40 pm

On these particular studs you can see the stretching quite easily. But that is useful info I'll keep in mind when I go in with the new ones.

thanks

Sat May 17, 2008 4:18 pm

Well installed the new studs today and everything went fine. The beam wrench is in fact necessary. I was lucky enough to have a veteran engine builder stop by the shop where my motor is. He mentioned the fact that even the factory studs stretch. Which then made it obvious to me that a click torque wrench will not click as the studs stretch which will lead to over-torquing and eventually the nut will bottom out on the stud. This in combination with the non heat treated studs made for a good learning lesson.

By the way, you can remove the studs with the cylinders in but they rub the cylinders which tears up the threads and makes them hard to remove. Luckily I learned this with the one I was removing. I rotated the crank and got the piston to tdc on each cylinder pulled the cylinder loose a little and installed the new studs.

Time to install the distributor and intake.

Wed Jul 16, 2008 8:26 pm

Wow. I can't believe how long it has taken me to finish this thing. I'll get some pics up tomorrow. My project took a lot longer as I cleaned and rehabbed almost every part of the engine.

I am now unemployed so I've got more accomplished in 3 days than I did in all the work before. Unfortunately my budget just got a lot smaller.

I have to set the end play tomorrow and install the flywheel and then I'm ready to reinstall the motor.

A couple more questions.
Where exactly does the felt ring go for the pilot bearing?

The throttle body looked like it had been soaked in grease and rolled in sand so I had to take the TPS sensor off do soak it. I reinstalled it today and want to double check the adjustments. The gray cam that actuates the switch has two lobes on each end. When the throttle is closed should one of the lobes be depressing the switch? Which brings up the next question. The adjustment screw for the butterly. For some reason it was gone from the throttle body. I read the bentley but was wondering if there was any more info considering my throttle body butterly seems a little worn. I've seen the post for tencent's fix but I don't want to do it right now. I need to get this thing installed and then do some fine tuning. I found a screw at a junkyard and would like to set it. Just follow bentley procedure? Or eyeball the butterfly and try and minimize gap around the edge?

Thanks
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Thu Jul 17, 2008 9:22 am

Quote: I read the bentley but was wondering if there was any more info considering my throttle body butterly seems a little worn. I've seen the post for tencent's fix but I don't want to do it right now.

Hey, man, you're unemployed. Now's the time!

Did you see the nice remachining whip618 did on his TB? Sweet.

That little stop screw needs to be there. The basic closed adjustment described in Bentley where the closed position is set by the degree of butterfly movement assumes that your TB is unworn.

Ha. That's a good one.

Anyway, you can start there, but the reason that adjustment is important is that there should be no vac signal at the nipple on the forward side of the TB when at idle. If there is, the EEC control valve will be opened and it will wreak havoc with the idle mixture.

So, the way to set it accurately is to do it on the motor using a vac gauge. There should be less than 1" Hg. vac on that nipple at idle. Adjust the screw to open the butterfly, you should see a vac signal, then back it off until the vac signal goes away. That happens when the butterfly goes past the tiny orifice inside the throat. If your butterfly is extremely worn, this may not ever happen, but using a vac gauge is how you tell if it's set right.

The little plastic cam for the TB switch closes the switch at idle position with one bump of the cam, and the other bump closes the switch as the butterfly nears WOT. It is the same signal seen differently by the ECU depending on the present rpms, mainly. You set the idle position; it is critical. The WOT closure then takes care of itself; it's not at all important exactly when the WOT enrichment comes on.

Thu Jul 17, 2008 8:52 pm

Took some bling shots with the cellphone today.

Finished installing exhaust headers today. Installing last bolt for the front header and noticed it wouldn't screw in. Threads stripped out in head. It's the lower bolt in the left in the pic. Pulled header, fix head tomorrow and install motor(crossing fingers). All the questions on the forum about how long it takes to do a rebuild now seem kind of funny. Depends on what goodies you find. All new parts, wouldn't take long.

I looked on another van and noticed it had studs on the exhaust ports on one side on the front and rear of the engine. It had bolts on the other. Does this sound right??