Chrysler - Low Compression on #2 - Head Gasket??

[turtle1173]

Hi all,<br /><br /> Some of you have been very helpful to me in dealing with my motor problems. Let me say first of all "Thanks so much" for all the help. <br /><br /> A few weeks ago I wrote about a 1972 85HP Chrysler that I had acquired. At the time, I didn't have any spark but I checked the compression and it was: 1- 130: 2-100: 3-126 The consensus seemed to be that it was probably stuck rings and would work out after I got it running. After all, it had been sitting for 10 years.<br /><br /> Well, thanks to all you guys, I got it running. I took her to the ramp today to give it a good running on my trailer and see how she shifted, etc.<br /><br /> To make a long story somewhat shorter, it seemed to be missing slightly and when I was adjusting the idle mixture screws on the carberators, it didn't have any effect on the #2 cylinder.<br /><br /> I got home & pulled the plugs. #1 & #3 looked wet but #2 looked like it did when I first put it in. So next I did a compression check. Here's what they were: #1- 127, #2- 72, #3- 126<br /><br /> My question is: What do I do now? Would this explain why it wasn't hitting on this cylinder? Could it still be stuck rings? If so, how do I deal with that? Please advise on how to procede.<br /><br />Thanks,<br /><br />Shane

 

[Solittle]

Re: Chrysler - Low Compression on #2 - Head Gasket??

Try to decarb the motor following the directions on the can. If that dosen't work I would not fool with it - part it out on eBay. It would cost far more to fix than it is worth.

 

[turtle1173]

Re: Chrysler - Low Compression on #2 - Head Gasket??

Hi,<br /><br /> What brand of DeCarb would be good to use for this? I'm assuming that I need to use the kind that you spray through the carbs. Is that right? I'm only familiar with Seafoam because there is a mercury dealer in town. Would they also carry the "spray" kind?<br /><br />Thanks,<br /><br />Shane

 

[turtle1173]

Re: Chrysler - Low Compression on #2 - Head Gasket??

Will the Decarbing work (through the carbs or in the gas), even though that cylinder is not able to fire because of the lack of compression?<br /><br />Shane

 

[Terry H]

Re: Chrysler - Low Compression on #2 - Head Gasket??

Turtle...you need to pull the head...prolly got a head gasket problem...easy task as long as bolts aren't stuck...just a Thought

 

[Ghost]

Re: Chrysler - Low Compression on #2 - Head Gasket??

If number two was dry it was getting no fuel. Even at 72psi it should have fired.<br />How long did you run it for, because if it was getting no fuel it was also getting no lubrication (gas oil mix)and you could have damaged the cylinder wall or rings. This would account for the lower reading from the first reading. I would disassemble that middle carb an check it out. It does not sound like a head gasket.

 

[turtle1173]

Re: Chrysler - Low Compression on #2 - Head Gasket??

Hi all,<br /><br /> I ran the motor for probably 15 minutes at idle. It would die whenever I tried to shift it into forward (Maybe that's a separate problem). I don't know that the plug was dry but there was no evidence of any burning, like on the other two cylinders. Perhaps I need to run it again to see for sure. Would that be a good idea??<br /><br /> I suppose the clean look on the #2 plug could be water. I hadn't really thought about that.<br /><br /> So at 72 lbs the piston should be firing anyway? Hmmmm, I just got the firing working, perhaps I need to check the fire on that one cylinder also.<br /><br /> I just had all three carbs taken apart and cleaned. I'm going to have to check and see if that #2 cylinder is dry or wet and just not burning.<br /><br />Thanks,<br /><br />Shane

 

[turtle1173]

Re: Chrysler - Low Compression on #2 - Head Gasket??

Hi again,<br /><br /> I just went outside to clean off all the plugs, so that I would be able to determine what is getting to the #2 plug (or not getting).<br /><br /> I hooked up the muffs to the engine and cranked her up for about 2 minutes. My muffs do a lousy job at securing water there, so I didn't let it run any longer (since I replaced the water pump only 2 days ago).<br /><br /> I pulled all three plugs and ALL 3 were burning and looked exactly the same.<br /><br /> Here's my analysis of the situation but I sure would like to hear what everyone else thinks. I'm guessing it is the head gasket and once the water starts flowing good, that #2 cylinder is getting water in it and therefore not functioning properly. Which would be why the plug looked new yesterday after running it for 15 minutes at the ramp.<br /><br /> I also failed to mention this earlier because I was not thinking about the head gasket being the problem. I can tell that the head gasket has been replaced before but the replacement has permatex all around as well. From what I read in my manual, this is a big No-No. So that leads me to believe that this has aided in my current problem.<br /><br /> Any comments??<br /><br />Thanks,<br /><br />Shane

 

[Terry H]

Re: Chrysler - Low Compression on #2 - Head Gasket??

Turtle...pull the head, it's real simple...you'll find out why someone put permatex on it...that way you can fix it right...just another Thought down the same old road

 

[turtle1173]

Re: Chrysler - Low Compression on #2 - Head Gasket??

Someone suggested to me that I should tighten the head bolts some and see if my compression went up any. I did this, checked the compression and it was even lower (62#'s). I pulled the head and sure enough, the metal ring seal on the #2 cylinder head gasket was broken on the bottom, thereby letting water into the cylinder. I thought this showed that the head gasket was my problem. Thoughts??<br /><br /> It was suggested that with my dipping compression #'s, it is a broken ring. I read in my manual that I can take the transfer port cover off, use a screw driver and lightly press on the rings and see if they have some give to them. If they bounce back freely, they are fine but if they don't, then the ring is probably broken. Anyway, I did this and they pushed in slightly and came right back. Does anyone know if this is a reliable test?<br /><br />Thanks again,<br /><br />Shane