wishbone

new engine has no power

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I have a new rebuilt six cylinder engine in my 1938 Packard.  I got it running, adjusted the valves (a couple of times), set the timing, etc... I've run the motor several times to bring it up to operating temperature in order to adjust the valves and torque the head properly.  I finally decided to give a little test drive and it just has no power to move the car.  At first I thought the clutch was slipping, but realized that releasing the clutch killed the engine...so the clutch is working just fine.  The brakes are new as well, but not sticking.  I figure it must be carburetor, but not sure.  Any thoughts on trouble shooting this problem would be welcome.

 

thanks, WB

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Hmmnnn...So are you sure your carb linkage is opening all the way? I've seen some where the gas pedal goes to the floor, but not adjusted to provide wide open throttle at the carb. Then, maybe, timing? Could it be a tooth off? Many will run, but just barely. Can you get more power out of it by moving the timing from the factory setting. Assuming good fuel flow, just a couple thoughts.

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I'll check that out.  I was wondering if the vacuum advance was leaky and effecting the carb and timing settings?  One thing that I forgot to mention is that when I adjust the low speed idle jet it has little or no effect. 

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I don't think the timing is a tooth off (hope not), but it runs and revs, albeit somewhat hesitantly.  I have to slowly rev the engine or it will die. 

 

thanks, WB

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Have you checked for a giant vacuum leak? If you "feather" it, can you get the rpm's up? As mentioned above, a compression check. Maybe a valve is too tight and not shutting all the way? Can you just bring it by the house?, lol!

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By "new" engine I assume you mean just rebuilt??

What does the engine do if you gas it too quick (besides die)---cough back thru carb ??? (too lean/not enough fuel etc)---backfire thru muffler/tailpipe??? (timing etc)...

HOW does it die??---sputtering/fluttering??---trying to run on two-three??---like you turned the key off??...

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Yep, rebuilt engine...machined crank, block, valve seats, head, and all new pistons, rings, bearings and seals.  New valve and valve guides also.  A professional did the machine work, while I (the hobbiest) did the assembly work.  I also made a new water distribution tube to replace the old funky steel one. 

 

Tommorrow I will do a compression and vacuum test as suggested.  That should yeild some insight.

 

thanks for the input...

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If it dies when you try to hit the gas, or stumbles, my FIRST order of business would be to check to see if there's an accelerator pump shot at the carburetor, and my second would be to check to see if the vacuum advance canister holds vacuum.  You can do both of these with the engine off.

 

Did you break in the camshaft correctly if it's new (or if the lifters are new)?  20 minutes at 1500+ rpm is typical.  Did you use good oil on the break-in?  Any valve noise right now?  Any missing?

 

Have you checked points dwell?  Vacuum leaks at the carb or manifold have already been mentioned.

 

Once I considered all these, I'd check compression.

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Yep, rebuilt engine...machined crank, block, valve seats, head, and all new pistons, rings, bearings and seals.  New valve and valve guides also.  A professional did the machine work, while I (the hobbiest) did the assembly work.  I also made a new water distribution tube to replace the old funky steel one. 

 

Tommorrow I will do a compression and vacuum test as suggested.  That should yeild some insight.

 

thanks for the input...

May I ask how you made a water distribution tube? I have a customer with a Chrysler 8 that can not find one.

Thanks

Dave

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Could be a hundred things. Cam timing off? Ignition timing off? Spark plug wires mixed up? Throttle not opening all the way? Carb messed up? Exhaust plugged up? Air filter plugged up?

 

The only thing to do is check everything systematically from start to finish. You will probably find some stupid little mistake that no one could guess in 800 years.

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I am a full blown master certified mechanic (small engines to diesels) and I was restoring a 62 Chev with a 409 with the same problem stated above. One day I got so mad I just floored the engine and something went bam!!. Now I have to pull the engine, I had a short temper back then. As I was pulling the water pump, there was a hole in the timing cover, I didn't tighten the timing gear bolts and that was the problem. Installed the cam gear correctly this time and it ran like it should. Fast and furious!!

Dave

post-121135-0-14396500-1442165668_thumb.

Edited by countrytravler (see edit history)

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Just a thought but in 1938 "regular" gasoline had an octane rating around 70 research. 87 PON is about 91 research and will need considerably more advance than 70 octane. Premium (93PON/97 Research) needs even more.

 

If set to 1938 factory specs you may be retarded.

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Well, I'll place my bet on the fact that some critters built a heck of a nest in the muffler. I've seen it before. You're describing the same symptoms that occur when a baffle comes lose in a muffler.

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Thanks for all the good input...especially about being systematic.  I just now finally found a few minutes to tinker on it again and decided to give it a compression test for starters.  According to my old rubber tipped compression tester I came up with some high numbers (130- 135 lbs.) on all but number six cylinder, which has maybe 10 lbs.... ugh.   130 seems a bit high, but I don't know what it should be.   Nonethelss, it is accurate enough to show that number six is goofy. 

 

I removed the rear valve cover to make sure that the valves were moving...and they are, but I ran out of daylight and time to get the engine warm again to reset the valve clearances. 

 

I'm hoping that it's a result of not setting the clearances with the engine running.  I did do it with the engine well warmed up, but by the time I got to number six maybe things cooled off enough to alter the accuracy.  Seems a little weird, though, that only one cylinder is way low...?

 

 

In answer to the question about the water distribution tube:  I used thin stainless steel sheet metal and made it in two pieces with continous soldered seems the length of it and a soldered cap at the end.  The seems where crimped as well.  I used the highest heat solder available.  I then copied the size and location of the holes from the original tube in order to allow for proper water flow around the cylinders.  The end towards the opening I just flared it enough to act as a stop to keep the tube from slipping all the way into the block.  I didn't know if it would work (and still don't really)...but he the engine has yet to over heat while running for perhaps up to an hour and a half maybe more.

 

thanks...

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In answer to the question about the water distribution tube:  I used thin stainless steel sheet metal and made it in two pieces with continous soldered seems the length of it and a soldered cap at the end.  The seems where crimped as well.  I used the highest heat solder available.  I then copied the size and location of the holes from the original tube in order to allow for proper water flow around the cylinders.  The end towards the opening I just flared it enough to act as a stop to keep the tube from slipping all the way into the block.  I didn't know if it would work (and still don't really)...but he the engine has yet to over heat while running for perhaps up to an hour and a half maybe more.

 

thanks...

Photos of that please !

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Update:  Like I posted earlier, after giving the engine a compression test (just the easiest first test for me to give), I discovered that it was extremely low on cylinder 6.  I then researched how to do a leak down test in order to discover "why" it was low.  I made up a tester and only applied 50 lbs. to each of the cylinders at TDC.  No. 6, as suspected did not hold pressure...very little at least.  I could hear air coming from the tail pipe and the adjacent spark plug hole.   Exhaust valve and head gasket it would appear.  I removed the head and everything looked just fine.  Cylinder walls still show cross hatching, valve appear just fine, and the head gasket was perfect.  My guess is that the head is not flat and therefore the gasket wasn't sealing (??).  As well I suppose the valve and/or valve spring need replace.  I don't have a valve spring tester, so I figure I'll just order new ones.  Also, I'm wondering if the valve guides might be a little tight??

 

A couple of notes about the head gasket:  I did not paint it with copper of aluminum paint prior to installation.  Also I put in new head studs, but some of them went in deeper than others...so with the new chrome acorn nuts and thick chrome washers, I suspect that the nuts didn't have as many threads for purchase as others.  I may for leave out the washer or use a thin grade 8 washer instead of the shiny thick chrome ones.

 

Anything obvious jump out at anyone?  Something else to check while I'm at it. 

 

thanks,

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Look real closely at the exhaust valve and seat on #6.  My logic is that if it were a head gasket between 5 and 6 you would have low compression on 5 also.  Hearing air in the exhaust obviously points at an exhaust valve.  I would take the head back to the machine shop that did the head and explain what you have done and ask them to check #6 and do a contact proof on the valve and seat.  A simple hand lap may fix the problem in short order.  Let us know.

 

R

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I came across a '50s boat with symptoms like that. The problem was that the carb was clogged with white powder after the petrol had all evaporated. After cleaning it all out it was fine. The thing would run on the idle circuit but not on the main jet. Opening the throttle caused a stumble or stall. The boat was in upstate Vermont and was stored during the winter when the lake is frozen over. For interest, it was a flat head 4 cylinder with updraft carb.

 

My 1930 DC Dodge does that too when it ices up in the carb. Is it possible this is happening? Solution is to idle it for 5 or 10 mins, shut down for 5 or 10 minutes while you fetch coat and sustenance for the trip, shut the garage etc. then restart and drive away in good shape.

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Did you even carefully check the valve clearance hot or cold? I'd say a valve clearance issue or sticking. Easy to check with the valve out.

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Hello guys, I have a 1949 Chrysler Royal.  I've owned it for a couple of years and I am still learning new things on it all the time.  I am trying to take the rear hubs off to check the brakes.  Which way do the bearing nuts turn to remove them?

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Hello guys, I have a 1949 Chrysler Royal.  I've owned it for a couple of years and I am still learning new things on it all the time.  I am trying to take the rear hubs off to check the brakes.  Which way do the bearing nuts turn to remove them?

I believe all of the nuts and bolts on the rear of your car are right handed threads except for the left side lug bolts/nuts.

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If the head bolts were replaced could some of them be protruding too far from the block  with the result that the "Acorn nuts" are binding on the  bolts and not allowing the head to be properly tightened?

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