Getting closer to figuring out what happened to my motor..... - The 1947 - Present Chevrolet & GMC Truck Message Board Network

Zumo · 08-02-2003, 07:44 PM

Looks like I may have "dropped a valve".
This pics seems to depict valve guide damage:

Zumo · 08-02-2003, 07:47 PM

Another pic.

I am in the process of taking the head off to send it to the machine shop to get it checked.

*racedvl* · 08-02-2003, 08:27 PM

Is the inner spring broken? I had broken a spring before, changed the spring, and she still running.

Class of 69 · 08-02-2003, 09:06 PM

The piece in his hand is the bronze guide, not part of a spring. I don't remember the engine history, or circumstances of the damage, but I hope the valve didn't hit the piston. Would take a serious hit on the valve face to force the stem to break the guide. It has obviously had exhaust leaking past the seat also, to be going up the stem. I will hope it's just a simple fix for ya!

Zumo · 08-04-2003, 10:24 AM

I hope so. I will be taking the head of this week to see if there is more damage. I reall hadn't had time to mees with it, although I did take the exhaust of this weekend. If I can save the head Ill send it to the machine shop.

beautimus · 08-04-2003, 07:54 PM

might not be a "dropped" valve as in broke it.
may be a case of "floated" one . like overreved and the spring couldn't return the valve to its seat in time and piston pushed it closed and bent it slightly, poping the side out of the guide.
i don't know the circumstances so its hard to say.
you may get lucky and find a small circular scar on the piston top, and a valve and guide that needs attention. or if your luck is like mine, a broken valve, a cracked head, and a busted piston .
good luck, Tony

Dandeluxe · 08-04-2003, 10:54 PM

Zumo,
this is wild that is almost exactly the same exact thing that happened to my 350 i pulled my head and it put an oval shape mark in my piston. it was on the passenger side at the no. 2 of valve intake on the no. 4 piston cylinder. i took the head to a machine shop and they told me it would cost 300 dollars they said i should just buy a new head so i think ill try to find a new head at the junkyard. and rebuild it im so sick of this crap im ready to throw in the towel and sell all . i think it's a test these trucks are a big test . oh well, DAN

jewels. · 08-04-2003, 11:37 PM

hey zumo, and all the others subscribed --- here is the original thread that zumo posted about his motor having problems --- you can read up on what happened:

Zumo's Motor Problem Thread a short while ago

beautimus · 08-05-2003, 03:24 AM

thanks jewels

well after reading the previous thread , i gotta say that blows my theory out of the water. i never heard of a valve doing anything like that just cruizin down the road.
i just can't understand how the keepers are still in place
and yet the valve guide is busted.
let us know what you find. this is a new one on me.
Tony

08-02-2003, 07:44 PM	#1
Zumo Hot Rods For Life Join Date: Sep 2001 Location: Waxahachie, TX Posts: 3,305	Getting closer to figuring out what happened to my motor..... Looks like I may have "dropped a valve". This pics seems to depict valve guide damage: __________________ 1968 C10 LWB **SOLD* Andy Viva Los Bicicletas! Los Muertos Custom Bicycles Last edited by Zumo; 10-04-2007 at 10:08 PM.

08-02-2003, 07:47 PM	#2
Zumo Hot Rods For Life Join Date: Sep 2001 Location: Waxahachie, TX Posts: 3,305	One more pics Another pic. I am in the process of taking the head off to send it to the machine shop to get it checked. __________________ 1968 C10 LWB **SOLD* Andy Viva Los Bicicletas! Los Muertos Custom Bicycles Last edited by Zumo; 10-04-2007 at 10:08 PM.

08-02-2003, 09:06 PM	#4
Class of 69 Registered User Join Date: Mar 2003 Location: Stillwater MN Posts: 1,166	The piece in his hand is the bronze guide, not part of a spring. I don't remember the engine history, or circumstances of the damage, but I hope the valve didn't hit the piston. Would take a serious hit on the valve face to force the stem to break the guide. It has obviously had exhaust leaking past the seat also, to be going up the stem. I will hope it's just a simple fix for ya! __________________ 69 GMC K10 ..some restoration required....still..

08-04-2003, 10:24 AM	#5
Zumo Hot Rods For Life Join Date: Sep 2001 Location: Waxahachie, TX Posts: 3,305	I hope so. I will be taking the head of this week to see if there is more damage. I reall hadn't had time to mees with it, although I did take the exhaust of this weekend. If I can save the head Ill send it to the machine shop. __________________ 1968 C10 LWB **SOLD* Andy Viva Los Bicicletas! Los Muertos Custom Bicycles

08-04-2003, 07:54 PM	#6
beautimus Registered User Join Date: Mar 2002 Location: woodstock, alabama, usa Posts: 938	might not be a "dropped" valve as in broke it. may be a case of "floated" one . like overreved and the spring couldn't return the valve to its seat in time and piston pushed it closed and bent it slightly, poping the side out of the guide. i don't know the circumstances so its hard to say. you may get lucky and find a small circular scar on the piston top, and a valve and guide that needs attention. or if your luck is like mine, a broken valve, a cracked head, and a busted piston . good luck, Tony __________________ i survived cancer and kidney stones, but my kids are killing me.

08-02-2003, 08:27 PM	#3
racedvl Account Suspended Join Date: Jan 2000 Location: Woodstock, IL Posts: 7,020	Is the inner spring broken? I had broken a spring before, changed the spring, and she still running.

08-04-2003, 10:54 PM	#7
Dandeluxe Senior Member Join Date: Nov 2001 Location: st.louis mo. Posts: 717	head damage Zumo, this is wild that is almost exactly the same exact thing that happened to my 350 i pulled my head and it put an oval shape mark in my piston. it was on the passenger side at the no. 2 of valve intake on the no. 4 piston cylinder. i took the head to a machine shop and they told me it would cost 300 dollars they said i should just buy a new head so i think ill try to find a new head at the junkyard. and rebuild it im so sick of this crap im ready to throw in the towel and sell all . i think it's a test these trucks are a big test . oh well, DAN __________________ 1969 cst swb 350/400 th . DANNY C . ["]FRIENDS DONT LET FRIENDS DRIVE F@RD$!! 1969 cst swb corvette hugger orange with 400 hp sbc I started out with nothing and i held on to it

08-04-2003, 11:37 PM	#8
jewels. Registered User Join Date: Jul 2001 Location: Munster, IN Posts: 1,100	hey zumo, and all the others subscribed --- here is the original thread that zumo posted about his motor having problems --- you can read up on what happened: Zumo's Motor Problem Thread a short while ago __________________ 68 C10 Red Step 350 my first child & main focus 58 3200 Apache LWB Step the upcoming project

08-05-2003, 03:24 AM	#9
beautimus Registered User Join Date: Mar 2002 Location: woodstock, alabama, usa Posts: 938	thanks jewels well after reading the previous thread , i gotta say that blows my theory out of the water. i never heard of a valve doing anything like that just cruizin down the road. i just can't understand how the keepers are still in place and yet the valve guide is busted. let us know what you find. this is a new one on me. Tony __________________ i survived cancer and kidney stones, but my kids are killing me.

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode



Register or Log In To remove these advertisements.

Register or Log In To remove these advertisements.