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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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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

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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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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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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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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?

John is correct, but I think you will have a better response with a new thread started. No bearing nuts in the rear. The nut holds the tapered drum to axle. Get a shop manual for your car if you are performing your own work. Only the front has a nut for the bearings. This is about an engine problem.

Make sure you have a heavy puller. Here is a video to remove rear drum that I made and yes, its amateur made.

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Did the shop check the valve seats for cracks? Did they insert hardened valve seats? If so, the exhaust valve seat may be coming out or not pressed in properly. Some shops do not, but I always lap the valves in to see that they are seating properly after doing a valve job on anything. Dandy Dave!  

 

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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  • 3 weeks later...

Hey all, thanks for the responses.  I finally had some spare time to get back to the Packard and it's low or no compression problem.  The leak down test pointed to the exhaust valve on cylinder number six as a possible problem so when I finally removed the head and look things over, I discovered that the valve was hitting the head (hammering it actually).  When the shop machined the head I guess they either took too much off, or it had been machined before and this time around it was just a little too much.  So it looks like I either have to track down another head (ebay...has a couple) or perhaps stack a couple of gaskets (??), or maybe relieve the area where the valves where hitting with a die grinder?  Along with replacing the bent valves of course.

 

Anyone ever relieve a head in this way?  Looks to be enough material there.

 

While doing this work, I also discovered the source of my coolant leak near the water inlet and it looks like I need a new water inlet housing.  If anyone has one, I'm in the market.

 

So mystery solved.  I'm glad I posted here though, because now I have a whole arsenal of good information for the next time I have a similar problem.  Thanks!

 

-E

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This is why when somthing is modifeid, (shaving of the head) have proftionals do the insulation. They would have check valve to head clearance with clay.

Glad that you have found the problem. No on the double head gasget. 409s use to do that on the high horse power engines but with steel head gasget. No go with a compound gasket. That is my opioin for the 60s engine and not with the older ones. Thanks for keeping us posted.

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OK so you have an "L" head (flathead) engine thathas been milled and the valves are striking the head, correct ? My notes say that is an aluminum head so first thing is to have checked for warp and cracks. OTOH since the original was 6.3:1 compression, raising it a bit for modern gas would not hurt if you have enough cooling for the extra heat generated.

So milling a valve relief in a sound shaved head should not be difficult, just make sure there are no sharp edges. Do you have a feeling for how much you need ?

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Finding a replacement would be the proper and easiest.

Clearance the valves would be the most fun.

As Dave suggested, use clay.

I don't know where I've heard it, and I've never tried it, but instead of using clay, use a tootsie-roll.
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I have struck a problem with valves hitting heads on side valve engines, sometimes the result of new seats sitting a little high and maybe valves with a little more meat than originals. Surfaced heads can contribute too. To solve the problem, take some material off the crown of the valve and the head can have a little material removed to create the clearance required.  I have never struck a head that is skinny on material in the combustion chamber so you should be fine to take as much as .030" there.  

 

Regards

Al

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Alrighty then, no double head gasket it is.  I am leaning towards relieving the head like some have said.  My car is not a show car or very valuable money wise...so doing a little experimenting might be fun and okay.  I think that I'll buy the head I saw on ebay anyways...just in case I screw something up.  If I end up using the new head, I'll do the clay trick before having it machined so the machinist will have an idea of how much he can safely take off.

 

thanks again, E

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Update:  Well, I've relieved the head above each exhaust valve by .010-.012.  It's more than what I need by a margin...let's hope.  One thing I started to wonder is:  with the head milled so far down, did I lose too much flow?  Would it be beneficial (or necessary) to relieve the block like the hot rodders do in order to regain some flow over to the cylinder?  Now is the time to do it...although kinda hard and messy doing it in the car.  The only reason I'm questioning it is because the compression on the other cylinders was so darn high (130-135 lbs).  I think this engine is suppose to have roughly 87 lbs. compression.  Obviously my gauge could be off by a margin, but 40 lbs more seems to be a clear indication that my compression has been significantly increased by the loss of transfer area in the head.

 

Any thoughts?

 

thanks,

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  • 2 weeks later...

Thought you said you had bought a spare stock head. Problem with milling the block is getting rid of debris you really do not want inside. I'd just give it a try but might take a liking to 89 or 91 octane.

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