Hydraulic Lifters Bleed Down Time

[petryshyn]

Re: Hydraulic Lifters Bleed Down Time

All engines will drop off in vacuum when under "load". Any engine problem will simply increase the drop.<br /><br />I would try power-timing first. That is the only way to time the old carbed 4-strokes. Don't worry about the hard start issue. If it runs better under full load WOT with the timing advanced further, but its hard to start, then its time to recurve the distributor.<br />If that doesn't help, I'd compare cam timing and lift. I've seen rounded off cam lobes that were hard to detect. Have you done a power balance at idle to determine if each cylinder is contributing equally? Compression can still read OK with a worn cam. The ugly thing is, we don't know whats in there for a cam....

 

[twwmm]

Re: Hydraulic Lifters Bleed Down Time

will be there tomorrow to try Power timing, and maybe extra fuel input to carb at wot, should be standard cam as it is counter rotating it would be hard to change. Unless wrong one put in by PO.<br />lift seemed ok when checked certainly no indication to worry about. Will try balance test as well.<br />Thanks

 

[WSUDERMAN]

Re: Hydraulic Lifters Bleed Down Time

Here is a thought for you...<br />What about Valve train float induced by weak/worn out valve springs? Or maybe incorrect spring rates?<br />I know, rare, but it would cause the symptoms you have...

 

[sho305]

Re: Hydraulic Lifters Bleed Down Time

The vacuum will decrease as load goes up until WOT and that is max for the engine. But the cam determines what air the engine will use at what rpm, so vacuum is good in powerband of cam normally idle to 5000rpm in a boat or so. Jumped timing will retard cam and make idle to 3500rpm powerband for example so vacuum above 3500rpm would be poor or not there.<br /><br />With twins you might get good holeshot pulling at 1000-2000rpm, but rolling on the power at higher rpm, say 3500+, would get much more power from the good motor. Vacuum would decrease as rpm went up compared to good motor for a given load. Vacuum same at idle, very different at 4000rpm.<br /><br />Sounds like that engine runs backwards you are saying. Make sure it has proper timing indicators or powertune as posted above. Then I would check cam timing, via rocker position? Not sure of easiest way, find a moving valve when timing mark goes by and compare to other motor? Remember it runs in reverse if it does when comparing. See if the valve begins/ends a movement at the same timing mark spot for each motor.<br /><br />If there is no water pump on the motor it is only a matter of using a puller on the crank pulley to get the timing cover off and find out for sure. Many older boats have few things on the front to remove. Hope this helps, gotta be an answer in here somewhere.

 

[Beernutz]

Re: Hydraulic Lifters Bleed Down Time

Any luck over the weekend?<br /><br />This has been a perplexing thread.<br /><br />Maybe the problem is that you're trying to run this motor upside down, over there on the other side of the world.

 

[twwmm]

Re: Hydraulic Lifters Bleed Down Time

Yeah, we have a lot of trouble keeping the fuel in the carb

 

[twwmm]

Re: Hydraulic Lifters Bleed Down Time

still checking, I still have to confirm the valve timing. I starting to think it may be a combination of a feww little things.<br /><br />I will keep you posted<br /><br />Thanks for your interest

 

[twwmm]

Re: Hydraulic Lifters Bleed Down Time

havn't fallen overboard (yet)<br /><br />I have checked the valve timing and it is correct, so thats not it.<br /><br />I have decided to change the lifters, as I am not in favour of cleaning them, any comments on cleaning ver replacement ?<br /><br />At the same time I will have a closer look at the spring, which will be next if the lifters don't help.<br /><br />Will keep you posted.<br />

 

[petryshyn]

Re: Hydraulic Lifters Bleed Down Time

if you still suspect the lifters cause they appear to be leaking down, I think that if this was the issue, they'd be noisy. <br /><br />>Have you tried adding fuel to the carb bore while under load via a squeeze bottle? This would rule out fuel starvation and make me feel a lot better! <br />>Have you power timed it yet?<br />>Have you checked each cam lobe for travel? (soft cam?)

 

[Mikael-Block]

Re: Hydraulic Lifters Bleed Down Time

Are you sure that engines are the same...??<br />Are you sure that Cams are the same, One ( Two) might have been change to other spec ?.<br /><br />Does the cabs second stage open ? Is it done by Vacum or mech....<br /><br />The only 318 I have seen was in my old 73 Dart. never done maintenance on it. <br /><br />mikael

 

[Beernutz]

Re: Hydraulic Lifters Bleed Down Time

Terry, if all of your lifters have collapsed, it sure would be awfully noisy down there in the engine room. It'd sound like a boiler factory!<br /><br />Are you experiencing anything like that?<br /><br />Does the rig have mufflers? If so, look for a broken baffle. Did I mention that your problem is baffling?

 

[petryshyn]

Re: Hydraulic Lifters Bleed Down Time

Have you checked your props? Are they a match?

 

[crazyray]

Re: Hydraulic Lifters Bleed Down Time

your problem motor is the counter rotating one? if so distributorand its advance mech inside would have to be opposite of reg rotating one.....can't swap one for the other and expect it to work is it possible previous owner replace dist and installled a reg rotation one. also the timing marks on front cover would be backwards....you maybe actually retarding the timing, that would cause a major difference in exhaust etc. also think you said you had swapped dist with no change, this would say that it is wrong,small block mopar reg rotation of dist when looking from above is clockwise. so your counter rotating one should be counter clockwise. to set distributor on your engine at dock get timing light with advance dial on back....set your timing to 32 degrees at about 3000 before tdc......don't worry about intial timing right now....any changes? if all this pans out has motor been overheated....seen another small block mopar that had been hot enough to have valve springs loss tension, owner had reringed it but had failed to check spring pressure, would idle great but not rev at all.....think I would get specs on cam and have a cam regrinder make a cam counter rotating and replace cam, lifters springs and all, also check your rocker arms be sure that not egged big time where shaft goes thru. seen these worn so bad that valve didn't receive half the intended lift of the cam .....the last is a reach seems it probably something more simple, feel for ya friend you have inherited a real problem child only way you may find it is to tear off in it see what you find......keep us posted

 

[crazyray]

Re: Hydraulic Lifters Bleed Down Time

one of other thing the design of mopar distributor drive is it pushes drive gear down on bushing under normal rotation...if counter then would try and push it up against dist.....if it moved much would change timing and the load on this shaft can be pretty severe at rpm from loading of oil pump...if thrust washers of distributor had failed could retard timing as load increased........