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Labor Day Putting down your wrenches or time for
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| | | | Joined: Feb 2017 Posts: 83 Vintage Truck & Tractor | | Vintage Truck & Tractor Joined: Feb 2017 Posts: 83 | I believe this confirms I need to have the head worked on. Here are my compression readings
Cyl. Dry. Wet
1. 150 150
2. 130. 130
3. 145. 140
4. 70. 70
5. 145. 145
6. 145. 145
#2 fouls a plug , I was surprised that 4 was so low.. It is a 235 in a 1962 C20. It puts out alot of blue smoke. I adjusted the valves.
What does this say to you experts?
Last edited by David C.; 07/07/2019 5:59 PM.
Current project; 1961 C20, 235 I6
| | | | | Joined: Apr 2002 Posts: 2,168 A teacher, but always an apprentice. | | A teacher, but always an apprentice. Joined: Apr 2002 Posts: 2,168 | Check to see if a rocker arm is compromised on #4. I had a similar problem on mine and it turned out that the rocker was cracked ( it later broke in two).
Or
Perhaps you have a burnt up valve? Bent rod?
Bad ring?
Last edited by Fox; 07/07/2019 6:20 PM.
| | | | | Joined: Dec 2017 Posts: 1,652 'Bolter | | 'Bolter Joined: Dec 2017 Posts: 1,652 | I Don’t know about that. Those compression values are not unusual for a 235 with the exception of no. 4. That one is low. If you can get access to a leak down tester, you might leak no.4 and see where the loss is.
Mike
| | | | | Joined: Feb 2017 Posts: 83 Vintage Truck & Tractor | | Vintage Truck & Tractor Joined: Feb 2017 Posts: 83 | I double checked compression on all cylinders. Re checked my tappet clearances too. Also checked #4 push rods. Not broken or crooked. Unless it isbemt and cant close all.the way I am at a loss. . I guess after the head is off it's only a few dollars more to inframe the rings and rod bearings. Like I said. The real riddle is 2 fouls a plug and 4 don't and it really smokes blue.
Last edited by David C.; 07/07/2019 9:12 PM.
Current project; 1961 C20, 235 I6
| | | | | Joined: Feb 2017 Posts: 83 Vintage Truck & Tractor | | Vintage Truck & Tractor Joined: Feb 2017 Posts: 83 | I put it all back togethor, ran it like I stole it then did the MMO thing down the throat
Half at fast idle.then let it idle and choked it down with the other half of the bottle. . I'll let it sit overnight .
Current project; 1961 C20, 235 I6
| | | | | Joined: Feb 2004 Posts: 29,740 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,740 | Air test all the cylinders BEFORE you remove the head. It's the only way to get a good check on the condition of the piston rings.
Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!
| | | | | Joined: Feb 2017 Posts: 83 Vintage Truck & Tractor | | Vintage Truck & Tractor Joined: Feb 2017 Posts: 83 | Ok. Don't seem like that would be hard to do. I'll give it a whirl and let you know what I get..
Current project; 1961 C20, 235 I6
| | | | | Joined: Dec 2008 Posts: 1,922 'Bolter | | 'Bolter Joined: Dec 2008 Posts: 1,922 | it's only a few dollars more to inframe the rings and rod bearings
More than that | | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | inframe
Never heard that term before. Looked it up and the meaning is obvious.
Thanks | | | | | Joined: Feb 2017 Posts: 83 Vintage Truck & Tractor | | Vintage Truck & Tractor Joined: Feb 2017 Posts: 83 | Keep your shirt on.
A "few dollars" is a relative term and just my manner of speaking. I know what things cost . This conversation is about diagnosing what exactly is causing the problem
Last edited by David C.; 07/08/2019 1:15 AM.
Current project; 1961 C20, 235 I6
| | | | | Joined: Dec 2008 Posts: 1,922 'Bolter | | 'Bolter Joined: Dec 2008 Posts: 1,922 | What a delightful rejoinder, how kind of you to take time from your busy day to share with me your innermost thoughts. | | | | | Joined: Feb 2017 Posts: 83 Vintage Truck & Tractor | | Vintage Truck & Tractor Joined: Feb 2017 Posts: 83 |
Current project; 1961 C20, 235 I6
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