Changed intake gasket, now it won't start
- Thread starter WSUTARD
- Start date
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brasil
Well-Known Member
I am sorry... but 125 to 155 psi is a big spread too much in my opinion 5 % is tolerable.. also the 9 inches of vacuum ...very low... ( or is it in 9 " in GEAR )
Greetings Juergen
Greetings Juergen
WSUTARD
Well-Known Member
Haha. Thanks, it's why I bought it. Figured I could handle engine stuff but didn't want to go though a $8k paint job.
WSUTARD
Well-Known Member
Well ok then. I read somewhere that 25% was the max variation. The vacuum was also 9 prior to me changing the intake gasket.
Any other opinions on the compression?
I guess I really do need to do a warm compression test.
WSUTARD
Well-Known Member
Ran compression while it was warm. Here are the results. Tighter than last time. Also, you will see that #1 and #6 are black. (5 and 7 have a header in the way).
j par
Well-hung Member
You have to get 5 and 7 out for sure and see what's going on there? Get something in there to break them loose even if you have to make something and then use a piece rubber fuel line push it over top of the spark plug and spin it out.
WSUTARD
Well-Known Member
Ohh I can get them out. Just don't want to...maybe I will tomorrow.
Why would #1 and 6 plugs be so black with the others normal?
How about we throw opinions out and go with FACTS???
(Opinions are like @ssholes, everyone has one and they are all full of ****...)
The 69 Dodge service manual states that there should be no more than 20 PSI difference between cylinders on a compression test...
Also, I would do a dry test, then a wet test where you put a few squirts of oil in the cylinder and then check compression. Compare the numbers wet to dry for each cylinder and see if there is any significant difference...
brasil
Well-Known Member
...if you want to make a compression test...you need a fully charged battery and all the plugs have to be removed...
the numbers you posted lately look a lot better !
Greetings Juergen
the numbers you posted lately look a lot better !
Greetings Juergen
WSUTARD
Well-Known Member
Finally got time to test compression on 5 and 7. (Stupid header). About 132 each. Both spark plugs where cracked, 7 had a white tip and 5 was black. Changed the plugs and it is running the same.
Best was to describe the sound is a rhythmic slapping sound. Blap blap blap. Just doesn't seem right. Still doesn't like to idle at 600-700.
Motor shakes a lot. Causes random "cavitation" sounds in the cab.
Doesn't have the power I expect.
Is the discoloration on the plugs telling me anything? 4 are perfect color, 3 are black sooty and one had a white (hot) tip.
Best was to describe the sound is a rhythmic slapping sound. Blap blap blap. Just doesn't seem right. Still doesn't like to idle at 600-700.
Motor shakes a lot. Causes random "cavitation" sounds in the cab.
Doesn't have the power I expect.
Is the discoloration on the plugs telling me anything? 4 are perfect color, 3 are black sooty and one had a white (hot) tip.
TrailBeast
AKA Mopars4us on Youtube
Half the cylinders on each back run off the opposing side of the carb base.
Problem is I don't remember if it was the two outer cylinders run off the opposite side, or the two inners.
I don't think plugs one and six have anything in common along that line though, but there is definitely something up with that plug pattern for sure.
Almost looks way out of time, or weak spark along with running way rich with an intake leak.
diymirage
HP@idle > hondaHP@redline
or weak spark along with running way rich with an intake leak.
misaligned rotor maybe?
6 and 5 are right next to each other, but 1 is across from it on the cap so maybe, maybe not
how old are the cap and rotor?
should be cheap enough to replace
j par
Well-hung Member
First of all this can't be from changing the intake gasket. Unless you did something like left a rag or something stuffed in side the intake when you are cleaning it? Without being there I'm just at a loss for ideas on how your motor could be running ok before the intake gasket and then running worse after fixing the intake leaks. Unless the car was Tune with intake leaks? IF it was me I'd be taking the motor out but I'm not suggesting you do that but just saying if it was me....
WSUTARD
Well-Known Member
Cap and rotor are brand new. When I first got it there was a bucking problem that I couldn't diagnose. My local shop figured out it was the distro and changed it and the cap. This was a month ago.
This time I also had them adjust the timing since I was out of town.
I was thinking weak spark as well but when I tested the spark it was a white blue color. Also one of the reasons a guy on here calls me "sparky"
This morning I went to start it up, started instantly, was on the choke and fast idle, but it was idling about 800, crapily. I let it sit there and idle and about a in minute the idle slowly started to pick up to the fast idle setting of 1300. The exhaust was a light white.
I'm just trying to provide any piece of info I can. Maybe it all connects for someone and can suggest something.
The next easy thing to try is to replace the carb jets and rods as well as the spark plug wires. But I am just guessing at this point.
WSUTARD
Well-Known Member
It is running worse, but still runs. Some people might think it is running fine but I can tell something is up. Pulling the motor might be a winter thing, last resort kind of option. I have never rebuilt a motor but my father in law has many times. Only issue is I have no equipment to pull the motor with.
Im going to try everything I can first. Thus the carb stuff and the plug wires. Plug wires are rather new anyway but it only sets me back the cost of the wires to try. They are way too long as it is now.
j par
Well-hung Member
I know Harbor Freight sells cheap motor stands and that's the big part. as far as a cherry picker I went so far as to get the motor always taken apart and ready to pull out and running down and renting one for Just 4 hours enough to pull out the motor and put it on the engine stand. Then go back and rented the day I'm ready to put it back in.
TrailBeast
AKA Mopars4us on Youtube
I think the one I got recently at HF for my small block but rated for beyond big blocks was about 70 bucks.
my first motor stand was an old tractor tire and 2 2x6's. used a chain hoist dangling from a tree to pull motors.
nm9stheham
Well-Known Member
Been way working for some days. OP, your cylinder compressions numbers are good. Contemplating pulling the motor based on what you show as compression numbers and the plug colors and symptoms makes NO sense.
The symptoms of running rough after replacing the intake gaskets twice still points to intake manifold leaks as one probable cause. The plug coloration likely indicates a mix of normal cylinder-to-cylinder variations and some degree of ignition and carb mistuning, in addition to intake leaks.
At this point, I would advise enlisting some local KNOWLEDGEABLE help or taking it to a local shop that knows these vintage of engines. Your have done a lot of work I know, but the level of good ideas seems to be dropping off; it needs a detailed and methodical process of troubleshooting. It has taken well over 100 posts to get to the point of a comprehensive set of compression numbers, and explaining how to go through a tuning process, figure out if there are still vacuum leaks, see if the 'blap, blap' sound is just exhaust leak, etc., is going to take several hundred more posts at the current rate. If your father-in-law builds engines, is he near enough to help?
The symptoms of running rough after replacing the intake gaskets twice still points to intake manifold leaks as one probable cause. The plug coloration likely indicates a mix of normal cylinder-to-cylinder variations and some degree of ignition and carb mistuning, in addition to intake leaks.
At this point, I would advise enlisting some local KNOWLEDGEABLE help or taking it to a local shop that knows these vintage of engines. Your have done a lot of work I know, but the level of good ideas seems to be dropping off; it needs a detailed and methodical process of troubleshooting. It has taken well over 100 posts to get to the point of a comprehensive set of compression numbers, and explaining how to go through a tuning process, figure out if there are still vacuum leaks, see if the 'blap, blap' sound is just exhaust leak, etc., is going to take several hundred more posts at the current rate. If your father-in-law builds engines, is he near enough to help?
j par
Well-hung Member
Agreed, and this is why I was saying started over again from scratch to take it out and start from the beginning LOL
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