Moparchat - Home of MOPAR enthusiasts worldwide!



Go Back   Moparchat - Home of MOPAR enthusiasts worldwide! > Technical Forums > Performance Talk

Click here to search for Mopar cars and parts for sale.


Reply
 
Thread Tools Display Modes
  #1  
Old 07-06-2006, 03:33 AM
Jim13's Avatar
Jim13 Jim13 is offline
Inactive User
 
Join Date: Jul 2005
Location: San Antonio, Texas
Age: 55
Posts: 451
Default Dead Cylinder

Took the dart out last night finally got my carb tuned correctly with the help of a couple of friends, and one of them says "it sounds like you have a dead cylinder" We start pulling spark plug wires and found out it was #6. I can't believe I never noticed it before.

It's geting spark and the plug was ok. I even put a new plug in it and checked it again. We pulled the valve cover and the spring looks ok and the valves are not stuck.

Maybe a valve is not seating properly?

Where do I go from here?
Reply With Quote
  #2  
Old 07-06-2006, 03:37 AM
72Challenger 72Challenger is offline
Inactive User
 
Join Date: Nov 2000
Location: Mission Viejo CA USA
Posts: 2,538
Default

Since you verified that you are getting spark, and that the valves are opening and closing, the next step would be compression and leakdown tests.
Reply With Quote
  #3  
Old 07-06-2006, 03:40 AM
dwc43's Avatar
dwc43 dwc43 is offline
Banned
 
Join Date: Sep 2002
Location: Shelbyville,Tn.
Age: 54
Posts: 23,987
Biggrin

I agree, leak down then compression check. You might want to pull the springs and check them for load. You can't tell by looking if they are good or not.
Reply With Quote
  #4  
Old 07-06-2006, 10:48 AM
Jim13's Avatar
Jim13 Jim13 is offline
Inactive User
 
Join Date: Jul 2005
Location: San Antonio, Texas
Age: 55
Posts: 451
Default

The compression check I can handle. How do you do the leak down test?
Reply With Quote
  #5  
Old 07-06-2006, 12:57 PM
cageman's Avatar
cageman cageman is offline
Inactive User
 
Join Date: Dec 1999
Location: Bismarck ND
Age: 46
Posts: 5,544
Default

close the intake and exhaust and pump some air in the hole, and see if it holds, or if you can hear any air coming up thru the carb or out the exhaust, you can narrow it down to exactly what valve then.
Check the plug wiring order too. Just last week I stopped at a guys house who was putting a 65 cuda back together and I heard a funny sound when it ran, for shits and giggles, I checked the plug wires and sure shit, it had two wires switched around.
Reply With Quote
  #6  
Old 07-06-2006, 03:26 PM
72Challenger 72Challenger is offline
Inactive User
 
Join Date: Nov 2000
Location: Mission Viejo CA USA
Posts: 2,538
Default

Here's a link that not only explains how to do a leakdown test but also how to build your own gauge:

http://www.xs11.com/tips/misc/misc3.shtml

If you're lazy you could by a used Snap-On for under $100 like I did.
Reply With Quote
  #7  
Old 07-06-2006, 03:34 PM
dwc43's Avatar
dwc43 dwc43 is offline
Banned
 
Join Date: Sep 2002
Location: Shelbyville,Tn.
Age: 54
Posts: 23,987
Biggrin

PRO-66839 Proform Dual Gauge Leakdown Testers
Leak Down Tester, Dual-Gauge, Each Today $65.69

TSR-14MMLDT
LEAK DOWN TESTER
7/12/06 $111.39

There's two from Summit Racing's web site. And a link to the cheaper one below.

http://store.summitracing.com/partde...5&autoview=sku
Reply With Quote
  #8  
Old 07-06-2006, 06:36 PM
Jim13's Avatar
Jim13 Jim13 is offline
Inactive User
 
Join Date: Jul 2005
Location: San Antonio, Texas
Age: 55
Posts: 451
Default

I'll get on it this weekend.

Thanks.
Reply With Quote
  #9  
Old 07-07-2006, 10:31 PM
Jim13's Avatar
Jim13 Jim13 is offline
Inactive User
 
Join Date: Jul 2005
Location: San Antonio, Texas
Age: 55
Posts: 451
Default

Just finished the compression test.

1. 105 ..................... 2. 110
3. 40 ...................... 4. 110
5. 125 ..................... 6. 40
7. 120 ..................... 8. 70
Reply With Quote
  #10  
Old 07-07-2006, 11:07 PM
72Challenger 72Challenger is offline
Inactive User
 
Join Date: Nov 2000
Location: Mission Viejo CA USA
Posts: 2,538
Default

Looks like 3 dead cylinders, not 1. Ouch.
Reply With Quote
  #11  
Old 07-07-2006, 11:47 PM
c318cuin's Avatar
c318cuin c318cuin is offline
Inactive User
 
Join Date: Feb 2002
Location: Castalian Springs Tn
Age: 43
Posts: 400
Default Hmmm

6&8 look like a blown gasket between the cylinders. So you might be "lucky" and have dead gaskets! I hope for you that is all it is. Good luck!
Reply With Quote
  #12  
Old 07-08-2006, 12:30 AM
dwc43's Avatar
dwc43 dwc43 is offline
Banned
 
Join Date: Sep 2002
Location: Shelbyville,Tn.
Age: 54
Posts: 23,987
Biggrin

Quote:
Originally Posted by c318cuin
6&8 look like a blown gasket between the cylinders. So you might be "lucky" and have dead gaskets! I hope for you that is all it is. Good luck!
Not meaning to hi jack the thread, but did you get a block from Dakhemi guy from Crosseville Tn. ??
Reply With Quote
  #13  
Old 07-08-2006, 12:46 AM
hpproron's Avatar
hpproron hpproron is offline
Inactive User
 
Join Date: Feb 2003
Location: New Braunfels, TX
Age: 55
Posts: 68
Default

Hey Jim...6 and 8 appear pretty obvious. It's the same symptom I had between 4 and 6. I showed you those pics in the e-mail....

Now...as far as ole' #3! Whooooooo-EEEEE! Just for shits and giggles, how many times did you do each cylinder? Could you have erred during the test if you only did it once? Did you use a screw-in gauge or a hand-held?

I only have a hand-held, so I make extra sure to let that needle comes all the way up, and then I retest the cylinder two more times and average the results. All of my cylinders were 186 to 193, except for the blown two. They read in at 54psi. Anyhow, sounds like alot of work, but it's pretty quick with a remote starter.

I'm sure some of the saltier old dogs here can come up with a better guess than I but sounds like #3 may have bad valves/seats, or piston rings if that compression test is positive. Definately do the LEAK-DOWN for better confirmation.
Shizzzz! Looks like we get to do a headgasket party together nonetheless! LOL! :P

I got some porting done today...should finish by tomorrow after work.
Attached Images
File Type: jpg _0011_resize.jpg (116.3 KB, 25 views)
Reply With Quote
  #14  
Old 07-08-2006, 02:05 AM
72Challenger 72Challenger is offline
Inactive User
 
Join Date: Nov 2000
Location: Mission Viejo CA USA
Posts: 2,538
Default

Apologies again to Jim for the hijack of his thread, but hey, hpproron? You're doing your ports with the valves installed?? How do you plan on getting all the crud cleaned out of the ports? I think you may be getting some unexpected valve grinding being done after you put it back together if you're not careful...
Reply With Quote
  #15  
Old 07-08-2006, 04:12 AM
Jim13's Avatar
Jim13 Jim13 is offline
Inactive User
 
Join Date: Jul 2005
Location: San Antonio, Texas
Age: 55
Posts: 451
Default

I did each cylinder twice with a screw in guage.

Looks like I'm pulling the heads huh?
Reply With Quote
  #16  
Old 07-08-2006, 04:33 AM
72Challenger 72Challenger is offline
Inactive User
 
Join Date: Nov 2000
Location: Mission Viejo CA USA
Posts: 2,538
Default

Looks like it. Hope it's not too serious.
Reply With Quote
  #17  
Old 07-08-2006, 11:06 PM
hpproron's Avatar
hpproron hpproron is offline
Inactive User
 
Join Date: Feb 2003
Location: New Braunfels, TX
Age: 55
Posts: 68
Default

Yes'sir 72...they are in place, so I WILL definately clean, clean and clean before it's all put back in. Both heads are done as of this evening. I just have to easy-out one of my exhaust studs then maybe do a quickie paint job. They are basically ready to go.

Good luck with that tear-down Jim! I, unfortunately, have been getting good at strippin my motor down...and that's not necessarily a GOOD thing!

Outa here for tonight....I'll be very curious as to what you see when the heads come off! Please keep us posted!
Reply With Quote
  #18  
Old 07-09-2006, 12:00 AM
Jim13's Avatar
Jim13 Jim13 is offline
Inactive User
 
Join Date: Jul 2005
Location: San Antonio, Texas
Age: 55
Posts: 451
Default

Retested tonight with the carb wired open and all spark plugs out.

1. 120................................2. 120
3. 45 wet test 50.................4. 120
5. 135................................6. 45 wet test 50
7. 125................................8. 90 wet test 95

It only went up by five. Is that acceptable to say my rings are ok?
Reply With Quote
  #19  
Old 07-09-2006, 12:28 AM
Crank Crank is offline
Inactive User
 
Join Date: Aug 2001
Location: Mich
Age: 65
Posts: 438
Default

pull the valve covers and pump up the bad cylinders and put a little oil around the valve guids and see if you can see air seeping threw or bleeding off.
Reply With Quote
  #20  
Old 07-16-2006, 12:25 AM
hpproron's Avatar
hpproron hpproron is offline
Inactive User
 
Join Date: Feb 2003
Location: New Braunfels, TX
Age: 55
Posts: 68
Question Hey JIM, what's the latest????

What do you know? Any luck on the tear-down.

I'm sure I'm not the only one who is still wondering what happened to you!

Ron in NB
Reply With Quote
  #21  
Old 07-16-2006, 09:54 AM
Jim13's Avatar
Jim13 Jim13 is offline
Inactive User
 
Join Date: Jul 2005
Location: San Antonio, Texas
Age: 55
Posts: 451
Default

I've been too busy to mess with it. Kind of bummed about it also, needed to step back and take a break.

Going on vacation next week to southern Missouri (Home). Figured I would just wait till I get back.
Reply With Quote
  #22  
Old 07-16-2006, 04:20 PM
cageman's Avatar
cageman cageman is offline
Inactive User
 
Join Date: Dec 1999
Location: Bismarck ND
Age: 46
Posts: 5,544
Default

Hey crank, quick question, But how would air get into the valve guides, are you compressing the intake or exhaust, I just figured that he was filling up the cylinder, and to me, I dont see how any air would get into the valve guides by doing that. If it has a burnt valve, you will plain as day hear it thru the carb for intake valve, and thru the exhaust pipes if it is the exhaust valve, and even if it had a burnt valve, I highly doubt any air would come thru the valve guides if this was happening, as it would take the path of least resistence and go out the carb or exhaust pipes, I doubt that you seal those two off to do this test.
You just got my curiousity going thats all.
Reply With Quote
  #23  
Old 07-16-2006, 09:05 PM
Crank Crank is offline
Inactive User
 
Join Date: Aug 2001
Location: Mich
Age: 65
Posts: 438
Default

my mistake but if you do a test squirt some oil on the valve guids when the valve opens to let the exhaust out or air in the guids will shoot oil back out or suck it in fast .that will tell you if the guids are shot and valves not seating.if you do this with the motor running it suck the oil in and smoke bad if intake valve is bad .exhaust will blow it back out. you ever seen oil running down the air cleaner thats usually bad rings blow by building up lots of presure in the crank case and sucking it up on the hose on the air cleaner or running out the breather cap.
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Dead 408 rlaman821 Performance Talk 2 02-20-2012 11:45 AM
1 dead cylinder. what should I do zzrck Ram Truck Chat 10 07-02-2003 08:10 PM
Dead cat at 38.5K NewBlackDak Ram Truck Chat 6 05-06-2002 12:03 AM
'92 Jeep Wrangler 2.5L 4-cylinder dead Curtis Jeep Chat (Wrangler, Cherokee, etc...) 1 08-01-2001 05:07 AM
Dead Ram, need hep! mada_dodad Ram Truck Chat 3 02-18-2000 10:53 PM




All times are GMT -4. The time now is 04:30 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
. . . . .