Since the compression test,which I did wrong, (throttle was open but the choke was closed),, I have come to realise that the carbutetor is flooding bad and has been for quite some time, probably since the carb was rebuilt. I think there was a lot of fuel in the sump. I removed the carb and found that allthough the needle and sets where working, there was a leak from the threaded part of the seat on one side, there is a copper seal under these and they dont seem to be thick enough for the new seat to seal. I replaced these with a rubber o ring from the carb kit and managed to solve that problem, I checked the float levels as close as I could and remedied another couple of problems in the carb. With new oil the engine is running and idling well, I think with no flooding. I need to do some more test drives to be sure. I reset the distribrutor timing with some advance. when I done the rocking test.
I still am unsure if my cam valve timing is correct but would presume it to be OK as the engine is low miles and there did not seem to be any slack when I done the rocking test.
poppy62,
Jul 12, 4:19pm
Great! that you have it sorted. I'm sure the valve timing is A OK, so don't go looking for trouble that doesn't exist. A fine tune of the Carb and Timing is all that is really required.
pdc1,
Jul 13, 8:38am
agree, however if you want to check, a vacuum gauge can give you a good indication of Valve timing being too far advanced or retarded. Google Vacuum Gauge tests. Also Valves on the rock on a number one, not on compression stroke, and at TDC will show that Valve timing is pretty close.
car__parts,
Jul 17, 5:48pm
Im sure I have the flooding fixed, it starts and idles well but only pulls up to about 2500rpm and then stumbles and wont go any faster. Any Ideas? EDIT I like the Idea with the vacuum gauge and will try that soon to try and check the valve timing.
neell,
Jul 17, 7:05pm
Go right back to the start of the problem. Was it running ok then suddenly started to act up? Was it running ok then slowly started to act up? Was it running ok and you did something to it then it acted up? Was it running ok and you "fixed" it and it acted up?
kazbanz,
Jul 18, 7:57am
I went to post what neel posted . I’d suggest going back to when it was running well to work out what changes you made or happened to make it run badly
budgel,
Jul 18, 2:03pm
If it is running ok but wont rev out, put a mark on the distributor body and where it bolts in (so you know where you are now) then loosen the distributor and move it towards the direction of rotation after turning the carb up to a fast idle. If the ignition is retarded it should speed up when you do this. I dont think it will be too far advanced if it is starting well. Make sure the vacuum advance tube is connected.
car__parts,
Jul 26, 1:11pm
I think if I go back to before the first post it was probably flooding bad then but was picking up in the revs ok and going a bit faster. Now I still have the problem, will rev freely when stationary to at least 3500rpm but will only do 2500rpm under load,and will stumble and if you keep the pedal in it it will strat to slow down and will sometimes stop. Have I done something in the thermoquad, Still starts and idles well.
peanuts37,
Jul 26, 1:33pm
Sounds like fuel starvation to me. Back firing through carb? Could also be over fueling, blocked air intake, air filter etc.
budgel,
Jul 26, 2:27pm
To get a correct diagnosis you have to eliminate potential problems one by one. 1) Do a compression test. is the compression up to spec? 2) Timing. there are two types of timing. Valves and spark. Make sure your timing marks for the cam line up. If you have to, take the cam cover off and make sure the cam mark is at 6 o'clock and the crankshaft one is at 12o'clock. Verify which mark the pointer is aimed at when set up like this.
Once you are certain the cam timing is OK, then establish that the ignition timing is good. Yours is at least at an ok starting point because the engine runs. Just for certainty check the firing order! Only after that, start checking the carb. Back in the day there was a standing joke that 90% of carb problems were electrical! Do these basics one by one. verify what is good and move on to the next thing. Eventually you will have the one thing left that needs to be sorted. It may well be the carb, but at least you will know for sure.
This method actually saves time in the long run. you wont be thrashing around on the next best guess, you will be working toward the conclusion.
strobo,
Jul 26, 5:36pm
Good point budgel pointed out re- the vacuum advance tube.
poppy62,
Jul 26, 9:17pm
Have you checked the plug leads? A resistance test would be well worthwhile. Quite a common fault often overlooked.
neldo8,
Aug 8, 7:41pm
I have a mid 70s 440 and read that to start them don't touch the pedal just turn the key seems to work better
car__parts,
Jul 8, 9:58am
My dodge 440 is in a 6 ton motor home with a 727 trans. It starts reluctently and then has no power when shifted into drive It will crawl forward about 1mph for a few metres then cuts out. It may be slightly better when cold and gets worse as things warm up. It has an electronic ignition. Carb rebuilt, new mechanical fuel pump. I took it for a drive, it run a bit for a while, I went to garage and fueled up and it was much worse, very hard to start and would only crawl. I played with it for about 1/2 HR and finally got it to move starting off very slow and building up enough speed to get home. What is the problem here? EDIT the problem has existed for quite some time now.
poppy62,
Jul 8, 11:31am
Can only be spark or fuel. I'd start with a compression test to eliminate valve and (possible) timing issues. Also gives you the chance to check spark plugs.OR. Auto choke may be stuck on, or Electronic ignition may have a fault. Is enough fuel getting through to the carb? Blocked fuel filter? or stuck float. All this if it's been sitting for a fair while. Stale fuel before you filled it up!
car__parts,
Jul 8, 1:14pm
I will need to check the fuel flow again as it has been a while since i did that. I have spares in the vehicle and have tried a different coil, and different electronic module and no change, still same problem.Probably not stale fuel, but I should check to see that there is no water in the tank, I am thinking timing issues and maybe the chain has jumped. I will do a comression test, but what would be the best way to check to see if camshaft timing is out.
mr340,
Jul 8, 1:34pm
sounds like it needs a new fuelpump pushrod. same thing happened to my 440
intrade,
Jul 8, 4:32pm
i would look for fuel in oil? = busted fuelpump membrane. a bypass and electric pump would be the fix and engine oil change if it has petrol in there now.
car__parts,
Jul 8, 5:43pm
Thanks Guys I have electric pump in line for priming, so have tried alernative fuel pump. The mechanical fuel pump is new.And appears to be pumping OK. I have not yet done a compression test,,, but set no 1 cyl with both tappets rocking, this coincides with the position of the rotor pointing to no 1 but the timing mark at the crank pulley is about 3/4 to 1 inch away from tdc,, could this be a jumped chain?
jmma,
Jul 8, 6:39pm
If tappets rocking that is not compression stroke so rotor shouldn't be pointing at No 1 should be opposite.
strobo,
Jul 8, 7:27pm
I agree Jmma & was gona say when I read that .Engine and ignition timing is everything! Tappetts need to be rocking on the last cylinder and that will leave no1 will be on the compression stroke.Then look where your rotor is pointing ,normally towards no 1 cyl then check where the crank timing marks are at for engine timing.Then set the engine timing @ 10 btdc ,then following set the base ignition timing accordingly to spec
poppy62,
Jul 8, 7:28pm
You can supply lots of the hot variety!
strobo,
Jul 8, 7:46pm
Could be brakes seized on too dragging ;-),could be many things.
strobo,
Jul 8, 8:07pm
You will want to pull the spark plug out of no1 cyl and establish true tdc .Insert a cable tie,pointy end works ok as an indicator)rest that on the piston top to indicate the rise and fall, then see where in relation the marks are on the crank ,they too should be on the tdc marks on the crank pully,if not a crank keyway may have moved or as you might think a timing chain worn ,if you turn engine anticlockwise then bring it clockwise slowly towards tdc the chain will lead without the lag,then back off anti clockwise and note any slack before the piston drops.while watching the cable tie indicator.the cable tie should drop as soon as the crank pulley is moved this would denote good chain tension .
car__parts,
Jul 8, 8:34pm
When I say tappets are rocking, I mean that they are loose and have clearance so as to say both valves closed. At this point the rotor lines up, but the crank does not.
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