valve compression weired!!!

[dmclean]

Anybody ever see this? I'm replacing my valve springs. I filled the cylinder to 100 - 115 lbs air pressure. Used a modified spring compressor. The spring dampers are a PITA big time.

When I compress the spring on the #1 exhaust valve, the spring, retainer, keepers, and valve stem all move but the cylinder stays at 100 lbs. How can that be if the valve moves? It should release the pressure out the exhaust port but doesn't.

Any ideas?

 

[dmclean]

Anybody ever see this? I'm replacing my valve springs. I filled the cylinder to 100 - 115 lbs air pressure. Used a modified spring compressor. The spring dampers are a PITA big time.

When I compress the spring on the #1 exhaust valve, the spring, retainer, keepers, and valve stem all move but the cylinder stays at 100 lbs. How can that be if the valve moves? It should release the pressure out the exhaust port but doesn't.

Any ideas?

I figured it out. It was the tool I was using. There was a check valve in the fitting at the end of the hose that the plug adapter screws onto. It only allowed the hose to be pressurized. I removed the valve and the cylinder pressurized normally.

 

[turbofabricator]

Good thing you caught that before you dropped a valve into the cylinder. Also, tap (or rather WHACK) each valve spring retainer with a hammer to break the keepers from the retainer. I just tap the edge of each retainer with a small ball-peen hammer.
When I was rebuilding BIG radial aircraft engines, we would use a 5/8" deep socket and smack it hard and the keepers would pop off into the socket. Easy/fast way to remove valve spring retainers/keepers.
I also use clips inserted into the keeper groves to keep the valve from dropping into the cylinder. Like this: http://m.grainger.com/mobile/product/GRAINGER-APPROVED-Safety-Clip-3LX83

 

[RmvBfrFlght]

What Ken said about the clips. I use a pair of long nose pliers with some rubbers bands around the handle. Once the spring is off clamp it onto the stem near the top of the guide. This way if you get distracted and lose air pressure the valve stays in place.

RemoveBeforeFlight

 

[turbodave231]

I you use the "Rope Trick" you won't ever drop a valve. Take a 5-6' piece of clothesline type rope and put most of it into the cylinder when the piston is in the middle of its travel. Slowly bring the piston to TDC by rotating the crank by hand. The rope holds the valves in place. No chance of dropping a valve.

 

[TurboTdr3.8]

What Ken said about the clips. I use a pair of long nose pliers with some rubbers bands around the handle. Once the spring is off clamp it onto the stem near the top of the guide. This way if you get distracted and lose air pressure the valve stays in place.

RemoveBeforeFlight

I use my needle nose vise grips if I plan to do something else when I cut the air off , works like a charm

 

[dmclean]

Thanks so much guys. I got the cylinders pressurized and found a bigger problem. The car has been sitting since 2002 and the valves leak like a seive. I'm going to pull the heads now and am not looking forward to it. Especially disconnecting the headers. Gotta do it though.

 

[Chuck Leeper]

Thanks so much guys. I got the cylinders pressurized and found a bigger problem. The car has been sitting since 2002 and the valves leak like a seive. I'm going to pull the heads now and am not looking forward to it. Especially disconnecting the headers. Gotta do it though.

May not be bad valves, only a bit of surface rust on the seats.
Remove the rockers, hit the valves on the stem, w/ a plastic hammer. This will snap the valves shut onto the seats. I see the leak issue when doing a leak down. I then use the hammer, and wala, they seal up...

 

[dmclean]

Thanks Chuck, I was just about to go out and start removing the heads. I'll try the hammer thing first.

Doug

 

[turbofabricator]

Agree with Chuck. But.......if you pull the heads, you can port them and put a real big smile on your face!!!!! Back in 1989 I swapped my heads with a set that were ported by AFR. Man........that was so cool!!!! I couldn't believe how hard it pulled mid range. I ran 11.77@112 with stock everything except heads/chip. Now days its real easy to run those numbers. Back then it was harder than a wood peckers beak to run an eleven. LOL.

 

[dmclean]

Thanks Chuck, I was just about to go out and start removing the heads. I'll try the hammer thing first.

Doug

I tried the hammer thing and it lessened the leakage but it didn't stop. already had the spring off the #1 intake valve and the seal held the valve from falling so I thought "why not stick the valve stem in a drill chuck and spin it lightly against the seat". Guess what.... It worked. no leak. I'm going to do the rest tomorrow.

 

[gunzandgearz]

Im with turbo dave , I used to use shop air and my hose from my leak down guage, but I was turned onto this trick with the rope from an old school fellow and it works.way better and not near as many hassles.

 

[dmclean]

Agree with Chuck. But.......if you pull the heads, you can port them and put a real big smile on your face!!!!! Back in 1989 I swapped my heads with a set that were ported by AFR. Man........that was so cool!!!! I couldn't believe how hard it pulled mid range. I ran 11.77@112 with stock everything except heads/chip. Now days its real easy to run those numbers. Back then it was harder than a wood peckers beak to run an eleven. LOL.

Thanks Ken, That thought has gone through my mind many times. The car belonged to my uncle who passed away 2 years ago. It hasn't run since 2002 and was stored in a fairly warm garage. I just replaced the whole fuel system (rust), tank to injectors, T chip and powerlogger, a complete brake system (rust) with stainless lines, new wheel cylinders, shoes, drums, pads, (rotors were OK). I found out why my uncle could never get it running. The chip that was in the ECM wasn't seated. It was in the socket crooked and the pins on one side weren't connected. Anyways, Ive dropped a fair amount of coin on it so far and just want to get it running. I can see the next problem will be with the PowerMaster brakes. I just want to get it back on the road and enjoy it for a bit before the snow comes. Headwork and header replacement will come later. Maybe over next winter. Then I can get that smile you were talking about.

By the way, I have a few of the safety clips and will try them tomorrow. I don't have needle nose vice grips... yet.

At any rate, Thanks to all for all the help. it's nice to know I'm not alone on this journey.

 

[dmclean]

Im with turbo dave , I used to use shop air and my hose from my leak down guage, but I was turned onto this trick with the rope from an old school fellow and it works.way better and not near as many hassles.

I hadn't heard of doing the rope thing until reading it here. How simple. Although I am glad I tried using air first or I wouldn't have known the valves weren't seating fully.

 

[dmclean]

Agree with Chuck. But.......if you pull the heads, you can port them and put a real big smile on your face!!!!! Back in 1989 I swapped my heads with a set that were ported by AFR. Man........that was so cool!!!! I couldn't believe how hard it pulled mid range. I ran 11.77@112 with stock everything except heads/chip. Now days its real easy to run those numbers. Back then it was harder than a wood peckers beak to run an eleven. LOL.

Well you got to me. After going back and forth as to port or not to port, and the fact that pulling the heads was not a pleasant job, I decided to get the heads ported. Mostly cleaning the cast marks and some bowl work. I should get them back next week. I'm still a couple of weeks away from starting it up for the first time in 13 years so now I'm looking forward to a bigger smile. Thanks for the encouragement.

 

[turbofabricator]

Good luck on your choice of porters. I spend more than 20 hrs on a set of Buick V6 heads to do them right. Of course a CNC machine will make short order of this, though.
Ported iron heads suck to port. Dirty, nasty work. Ventilation, respirator, face shield, hearing protection, and lots of good lighting makes for a miserable existence. After 30 years I think I just finished my last set.

 

[SPOOLFOOL2]

My trick has been to use compressed air and a wooden clothes pin to hold the valve up.

Mike Barnard

 

[gunzandgearz]

Yea I don't blame you turbofabricator a good friend of mine by the name of Trent Townsend who use to port heads with the late great Lee Shepard at Reher Morrison and up till a couple of years ago was doing all the induction systems {heads and intakes} for Larry Morgan totally quit porting iron heads about 15 years ago because of how tuff it was on him. Hopefully you don't end up with carpultunnel.

 

[dmclean]

Good luck on your choice of porters. I spend more than 20 hrs on a set of Buick V6 heads to do them right. Of course a CNC machine will make short order of this, though.
Ported iron heads suck to port. Dirty, nasty work. Ventilation, respirator, face shield, hearing protection, and lots of good lighting makes for a miserable existence. After 30 years I think I just finished my last set.

Hello turbofabricator. I just noticed the "like" you gave me. thanks. I got my heads back and the shop that did it (D and D Performance in Chesterville Ontario) is working in another turbo engine and are doing work on some aluminum heads and installing an RJC Girdle. They have a great reputation. They found one of my heads was out by 8 thou and the other by 9 thou, fairly large for short heads. Now I'm really glad I took your advice. Right now I'm just buttoning up the motor installing the new fuel lines and should be ready to start it by the end of this week. Fingers crossed.