hchris

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Posts posted by hchris


  1. 4 hours ago, gregchrysler said:

    Help me again   I have a 49 Chrysler 251 cc  single barrel carb  that works fine on idle and when I rev up engine gets a loud pop.  Firing order ok all cylinders firing sounds fantastic til I rev it up.  New rebuilt carb on it   any ideas

     

    Lean mixture it sounds like;  as well as the other answers, there might be an air leak through the carb base gasket or inlet manifold gasket; perhaps re tension all the mount bolts / nuts ?


  2. 3 hours ago, Mpgp1999 said:

    I believe all cylinders are firing properly however cylinder 1 has very little compression.

     

    Alright, now we might be on to something. The thing of significance is the #1 low compression, the vac guage is never going to be steady if you have a large variation in any cylinder compressions, this would have been a tell tale pointer from the get go had you mentioned it in the beginning. To develop full power and smooth running you need to have minimal variation between all cylinder compression readings.

     

    So with that in mind how low is low, do you know what the compression pressure is on #1 cylinder ?

     

    Just off the cuff, an incorrectly set valve clearance (or leaking valve due to poor seating) will give you wild vacuum fluctuations, and low compression. So a question to be answered, were the valve clearances adjusted after the timing chain / gear episode ?

     

    7 hours ago, Mpgp1999 said:

    I am not sure what you mean by the vacuum numbers

     

    The numbers on the guage face, I was trying to establish what range the needle of the guage was moving to / from in vacuum reading not psi. So would I be right in assuming the guage is bouncing from one end of the scale to the other at steady idle rpm ? OK don't answer this I re read your earlier post.


  3. 8 hours ago, Mpgp1999 said:

    By putting my finger over the hole I can feel air being sucked in and maybe blownout.

     

    I don't understand where this hole is ?

     

    And yes we are a little confused at your references of psi and vacuum, it would be easier if you just tell us the vacuum numbers.

     

    Also I am curious as to where you have the guage hooked up.


  4. 10 hours ago, Mpgp1999 said:

    The gauge needle is constantly moving at a rapid pace 

     

    Q1. Is this happening at steady idle speed ?

    Q2. What is the magnitude of fluctuation, what are the numbers its fluctuating between ?

    Q3. What are the indications at a steady high engine speed ? 


  5. 7 hours ago, Mpgp1999 said:

    Are the numbers the same for my engine?since it is an older engine can I use a modern gauge?

     

    As others have stated the vac readings are pretty much standard for all engines; if you were to modify things like the cam then readings would be different, we assume not so in your case.

     

    Given that you have had timing gear / chain issues I would expect that the vac readings would be steady but lower than the ideal 18".

     

    It is important that you connect your vac guage line to a vacuum source which is unrestricted and below the throttle in terms of air flow, ideally this would be into a blanking plug on the intake manifold, if you are using some other source make sure there are no restrictors at the connect point, and yes do report back on your findings before you rip into it.


  6. 6 hours ago, nearchoclatetown said:

    You now have had someone install a new cam gear, it MIGHT be out of time. That will cause the problem you describe. You need to verify that it is on the marks, that the cam is timed correctly. THEN worry about the ignition timing. Did you ever install the condenser from Budd Lake? An easy way to check on cam timing is with a vacuum gauge. Find a chart online that explains the readings from a vacuum gauge and FOLLOW the instructions.

     

    Given the info you have put up, the above would be high on my list of causes and before you pull anything apart do the vac guage thing, you should have about 18" steady vac reading at idle. If you are not familiar with this method of diagnosis do as suggested, find an analysis chart online, it is a very easy way to verify timing (both cam and ignition).


  7. On ‎21‎/‎12‎/‎2016 at 8:39 AM, 1956BuickSuper said:

    Thank you for all your help! 

    Something that I didn't mention, and I don't know why I didn't, but the cutout relay in the voltage regulator closes whenever I connect the battery to the car again. Hopefully that is of some help. And when I start the engine the ammeter needle goes off the scale, to the extreme right. 

     

    Whoa, that's not right, get the alternator checked out; you may have flashed a terminal / wire whilst refitting, and the amp meter is telling you that its not right. 


  8. 3 minutes ago, hidden_hunter said:

     

    Interesting, it's pretty common the buick scene to remove it, guess I'll leave it on my 22 and see how it goes. Don't think I'll want to do too much driving when it's 110 out

     

    Yes as I said it cuts both ways, manifold heat is a pain in summer but an asset in winter. I guess if nothing else this discussion highlights an often not understood aspect of todays fuel issues with our older cars.

     

    Just as an aside, if you really need to raise your awareness of cold weather piston engine fuel issues, open up a manual for light aircraft pilots; probably one of the most common causes of aviation mishaps is throttle icing, summer and winter.


  9. 2 hours ago, Jim Bourque said:
    2 hours ago, Jim Bourque said:

    In the 1920's gas was closer to kerosene. That's why carbs/intake manifolds were heated, the heat vaporized the gas. Today's gas does not need or want the heat.

     

    As far as carb icing in Phoenix AZ, I doubt there is enough moisture in the air for that to be a problem.

     

    As another poster on these forums says "90% of carb problems are ingnition related".... verify your ingnition system is working as it should, you may have more than one issue. 

     

    I am not a fan of electric fuel pumps on carbs that were designed to run a vacuum fuel pump, especially on a carb as finicky as the Johnson/Cadillac. If you need parts for your carb, Classics and Exotics has Viton tipped needle and seat, gaskets and a modern material float that are top quality. If you are not comfortable rebuilding your carb, they can do it for you.

     

    I hope you get that beautiful classic back on the road soon

     

    Jim

    In the 1920's gas was closer to kerosene. That's why carbs/intake manifolds were heated, the heat vaporized the gas. Today's gas does not need or want the heat.

     

    As far as carb icing in Phoenix AZ, I doubt there is enough moisture in the air for that to be a problem.

     

    As another poster on these forums says "90% of carb problems are ingnition related".... verify your ingnition system is working as it should, you may have more than one issue. 

     

    I am not a fan of electric fuel pumps on carbs that were designed to run a vacuum fuel pump, especially on a carb as finicky as the Johnson/Cadillac. If you need parts for your carb, Classics and Exotics has Viton tipped needle and seat, gaskets and a modern material float that are top quality. If you are not comfortable rebuilding your carb, they can do it for you.

     

    I hope you get that beautiful classic back on the road soon

     

    Jim

     

    Where I live its recognised as the driest state in the driest continent on this planet, I can assure you that in the middle of winter I suffer occasionally from throttle ice.

     

    I wouldn't discount ignition or any other problems for that matter, but if I was suspecting fuel the above posting explains the probabilities.


  10. 3 hours ago, hidden_hunter said:

     

    Does it really need the manifold heat with modern gas? 

     

    Absolutely, the properties of todays gas are designed to function under high pressure for injection systems. Essentially the fuel is properly atomised in the region of 80psi and sprayed into the cylinder thru precision orifice nozzles.

     

    A carb atomises fuel thru the low pressure area of the venturi just above the throttle plate, nowhere near as effective as a high pressure pump; the then (marginally atomised) fuel passes thru a convoluted, and this case cold, manifold before getting to the cylinders, along the way the cold fuel in contact with a cold manifold turns back to liquid and sticks to the walls of the manifold. Hence flooding and poor running are the usual characteristics. So in this instance manifold heating is desirable, up to a point.

     

    Of course the down side of our primitive manifold heat mechanisms is during the summer, where they become too effective and over atomise - read vaporise - the fuel and we suffer from vapor lock, this is I suppose the price to pay running old cars on modern fuels. :)


  11. 14 hours ago, BillhymerMD said:

    Thanks for all the info.  I'll have a look at the float and see if I can't work through the issue.  Not a lot I can about the fuel.  

     

    About the fuel, the higher octane rating you have the better it will atomise; yes amongst other things the reid vapour pressure is all about how well certain fuels perform at different ambient temperatures. When its available spend the money and always go with the highest rated fuels, you might be surprised at the difference in running.


  12. 20 hours ago, Spinneyhill said:

    I would have thought the manifold heat valve was irrelevant to cool running. It is only meant to warm the carb. to stop icing in the venturi.

     

    Did all these bad things start happening at the same time? i.e. one problem or several.

     

    The manifold heat valve promotes a better atomising process during cold running; if its stuck in the open position there is no heating of the manifold, fuel condenses and pools on the cold induction manifold walls and doesn't reach the combustion chamber in an atomised form, the net result is poor running and flooding.

     

    As to icing in the venturi, you need a source of warm air entering the carb intake to prevent this, the manifold heat valve is below the venturi.


  13. 11 hours ago, 1Aries said:

    happy black friday.34 Dodge pilot bearing question:

    I have the tranny out and now considering clutch, throwout bearing and pilot bearing issues.  Clutch has been working fine, throwout brg seems fine and adequately lubed but can't say anything abut the pilot bearing.  Do I use a puller for that? and.. is it continuously lubed like the T/O Brg.?

     

    No its not lubed in service, the bush material itself has a lubricating property. If its worn do as suggested above, in fact even if its not worn now it will be in the future, so whilst its all apart best do it now.

    • Like 1

  14. 4 hours ago, BillhymerMD said:

    Since the weather cooled my 29 Cadillac is running poorly.  The engine ran great all summer when it reached an engine temp 170 -185F.  Now the engine only reaches a temp of 140 - 155F and the engine has been flooding, car backfiring and all around running terribly.  The car has an electric fuel pump with fuel regulator placed many years ago, regulator set at lowest setting.  I placed another inline fuel regulator thinking too much fuel was the problem because the car was puking it all over the road but I still have the problem even though I've limited the fuel significantly from the pump.  Maybe it's the fuel?  Or perhaps its because the thermostatic controller isn't working to heat the engine up?  Any ideas appreciated.  

     

    A  few thoughts, not in any particular order:

    • are you using premium fuel ?
    • having just changed seasons; fuel companies switch blends for summer to winter, so its possible you may have the last of a summer blend which wont atomise thru the carb now that the air temps have dropped.
    • get some more heat into the engine, even if you resort temporarily to blanking off the lower half of the radiator
    • if you have a carb/manifold heat valve make sure its working properly

    ;)

     


  15. 14 hours ago, keiser31 said:

    This is what you need along with sledge hammer....make sure it's not a Chinese tool or the tool will break. Be certain you adjust the brakes inward away from the drum prior to removing drum.

     

    Quote

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    Just my two cents, even with the correct tool don't expect it to come straight off, depending how long its been installed you may have to progressively put tension on give it a wack then go and have a coffee before the next blow. I have had a situation where it took a couple of days to get one off; oh and a word of caution, leave the axle nut on a couple of threads so that the drum doesn't fly across the shed when it lets go. 


  16. 1 hour ago, ckowner said:

      The timing light is great, but the 1930 engine does not have a timing mark. To set Ignition timing the 1930 DeSoto Finer Six instruction book reads as follows:

     "The breaker points should be adjusted to .020" (.508 mm.) opening. The 1/8" pipe plug should be removed from the cylinder head above #6 piston and a gauge rod placed through the hole and in contact with the piston head. The crankshaft should be rotated until No. 6 piston is coming up on exhaust stroke and stopped when the piston is .009" before TDC. The screw which clamps the distributor timing lever to the distributor should be loosened and the distributor cap removed to see that the rotor brush is at #1 spark plug cable terminal. The distributor clamp screw should next be loosened and the distributor rotated in an anti-clockwise direction , as viewed from above, until # 1 cam begins to separate the breaker points. Before doing this the distributor rotor should be pressed against the direction of rotation to be certain that all backlash is removed. The clamp screw should then be tightened and the distributor cap reinstalled as well as the spark plug cables connected to the proper spark plugs and terminals on the distributor cap"

     It may be possible with modern test equipment to by-pass this process, but I decided to build this tool and follow instructions, and it works!

     

    No argument with that, that's how the engineers of the day wanted it.

     

    Without wanting to labor the point, I am saying that there are other factors today which could make a rigid timing setting less than ideal, modern fuel properties being just one of them and then of course, the wear and tear of an older engine with its knock on effect of timing gears/chains etc.

     

    Establishing an exact by the book timing point is not absolutely necessary to have an engine run efficiently, its a starting point which can then be refined to suit the particular needs of any one engine.

     

    As to not having a timing light, you might like to consider setting the timing with a vacuum guage, its a very reliable and accurate method of getting the best out of an engine with regard to ignition timing.

    ;)

     


  17. Excellent tool, no doubt that you could get pin point accuracy with it.

     

    But the problem remains with getting that stubborn plug out without causing grief; the purpose in using this access point is usually associated with getting a starting position for initial ignition timing, different matter if we are talking valve timing. The fact still remains that there are other reasonably accurate ways to achieve initial timing.

     

    Lets not forget that ignition timing settings are a guide to best engine performance, every engine is different, fuels are different to way back when, pulley timing marks are subjected to such things as timing chain wear, softened rubber in the crank damper etc. etc.

     

    Summarising all of the above; setting the ignition timing is only a guide, you don't have to be precise at the initial timing point, the quoted figures are there to get you started and then the fine tuning can commence based on road tests, timing lights or vacuum setting (which I find most successful). 


  18. Glad you got it sorted, this is an oft repeated problem with side valve engines, where a probe over the piston is not going to work because the spark plug hole is over the valves, not the piston, hence the need for a removable witness plug which is invariably corroded in place; by the way in your case just cut an appropriate length of similar threaded bolt as a replacement, cut a slot in the top and screw it in.

     

    So a couple of other points to make when you cant determine TDC with a probe and you do have access to the valve lifters. At TDC #1,  both the inlet and exhaust lifters should be slack, that is no tension on the valve springs (valves are closed), at the same time (with a 6 cylinder) the #6 lifters should be rocking - exhaust just closing and inlet just opening. So in summary, turn the engine by hand in direction of rotation and watch the movements of the #1 and #6 lifters, it takes a little finessing and you may have to go a couple of rotations to get it right but in the end you will be within a few degrees of correct positioning, the emphasis needs to be on watching the #6 lifters rather than #1, and in the case of an OHV watch the rocker arms.

     

    With regard to misplaced distributors, a lot of time can be saved if you consider where the #1 spark plug lead needs to be when #1 piston is at the correct timing point. It doesn't really matter where the distributor or cap are placed, the critical element is with the rotor, wherever it is pointing when #1 is ready to fire, that's where the #1 plug lead needs to be positioned  in the cap; the rest are positioned to follow suit, such as 153624. So if you know which way the distributor rotates, position the other wires accordingly, it may look wrong asthetically and you may have to move wires to reach, but if the alternative is removing the sump and re keying the oil pump I know which option I would choose.

    :D