99 problems and a Ford ain't one.

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VonCramp

VonCramp

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A couple of months ago I posted some issues I was having with my 340. I thought I had sorted them out by adjusting the valves. In all fairness the car tricked me. Because if I drive it, that's when it all goes to ****.
It will run beautifully for about 15 minutes. I take it on the road, and it starts loading up like it's getting too much fuel. The oil pressure drops. Idle drops. Power drops. I could surmise here everything I think could be wrong. Instead, I will tell you what's new and done to this p.o.s. motor.
New blue ignition box
New Moroso plug wires.
New Champion plugs
New intake gaskets
New resistor
.Stuff I did.
Trunk mount battery (hard to start when hot)
Pro Comp alluminum heads
.070 Cometic head gaskets (.024 deck height on pistons)
Solid roller cam (flat tappet Crane disintegrated)
Comp Cams extreme pressure valve springs
Pro Comp roller rockers (die grinder clearanced for springs)
Jegs electric Holley style fuel pump (Shitty Holley pumps leaked/ or just quit)

I have noticed that sometimes #1 exhaust, #4 & #6 exhaust stay cold even after car is warmed up.
Sometimes they operate normally. Fuel pressure reads 12.5 psi no matter the regulator or pump. I gave up on troubleshooting that crap. Car seems to not care most of the time anyways. I posted a video of it idling normally on youtube. I can provide a link if anyone cares. Wondering if when my hydraulic flat tappet cam died that caused damage? Cold idle I have 40 psi. Hot idle is 5 psi but climbs with rpm. I am at my wits end with this damn 340. Never spent so much money to have something run so horrible.

20200410_182423.jpg
 
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Let’s start with the previous cam situation. What exactly happened there? Bad break in? Did you tear the whole engine down and clean everything out? To me, unless you tore the whole engine down after it wiped out I’d assume it’s going to **** things up. Again, 5 hot idle is a bit of a worry to me, unless you set you bearing clearances loose?
12.5 is a lot more pressure that I’d like to see, I’m sure it’s pushing through the seats. Looks like you’ve got a few things to take care of but I’m sure with the genus’s on here you get it figured out I no time.

Jake
 
VonCramp said:
A couple of months ago I posted some issues I was having with my 340. I thought I had sorted them out by adjusting the valves. In all fairness the car tricked me. Because if I drive it, that's when it all goes to ****.
It will run beautifully for about 15 minutes. I take it on the road, and it starts loading up like it's getting too much fuel. The oil pressure drops. Idle drops. Power drops. I could surmise here everything I think could be wrong. Instead, I will tell you what's new and done to this p.o.s. motor.
New blue ignition box
New Moroso plug wires.
New Champion plugs
New intake gaskets
New resistor
.Stuff I did.
Trunk mount battery (hard to start when hot)
Pro Comp alluminum heads
.070 Cometic head gaskets (.024 deck height on pistons)
Solid roller cam (flat tappet Crane disintegrated)
Comp Cams extreme pressure valve springs
Pro Comp roller rockers (die grinder clearanced for springs)
Jegs electric Holley style fuel pump (Shitty Holley pumps leaked/ or just quit)

I have noticed that sometimes #1 exhaust, #4 & #6 exhaust stay cold even after car is warmed up.
Sometimes they operate normally. Fuel pressure reads 12.5 psi no matter the regulator or pump. I gave up on troubleshooting that crap. Car seems to not care most of the time anyways. I posted a video of it idling normally on youtube. I can provide a link if anyone cares. Wondering if when my hydraulic flat tappet cam died that caused damage? Cold idle I have 40 psi. Hot idle is 5 psi but climbs with rpm. I am at my wits end with this damn 340. Never spent so much money to have something run so horrible.

View attachment 1715525297
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If you had to grind on your rockers the geometry is wrong. Just an FYI.

Why is the fuel pressure so high? Is it a dead head system or a bypass system?

Your oil pressure issue is worse than the fuel pressure issue.

5 pounds of oil pressure at idle is just wrong. Why is the pressure so low?

You have some serious issues that need to be addressed...pronto.
 
Wiped cam....5 psi hot...cold exhaust. Like Jake said that doesnt sound good. If it was mine I would be tempted to pull it.
POS 340? I understand frustrations but that adjective might be saved for elsewhere(machinist/advisor etc...lol)
Also why battery in the trunk?
 
4spdragtop said:
Wiped cam....5 psi hot...cold exhaust. Like Jake said that doesnt sound good. If it was mine I would be tempted to pull it.
POS 340? I understand frustrations but that adjective might be saved for elsewhere(machinist/advisor etc...lol)
Also why battery in the trunk?
Click to expand...

Let me go a step further and say it would already be on the stand. Like it or lump it the pin is probably pretty close to coming out of the Hand grenade... Sux but this is Hotrodding and it will get figured out...

JW
 
Your fuel pressure is way too high, as others said. Could have led to thin oil, which might contribute to low idle pressure. How do the plugs look? Post pics!
 
xLURKxDOGx said:
Let’s start with the previous cam situation. What exactly happened there? Bad break in? Did you tear the whole engine down and clean everything out? To me, unless you tore the whole engine down after it wiped out I’d assume it’s going to **** things up. Again, 5 hot idle is a bit of a worry to me, unless you set you bearing clearances loose?
12.5 is a lot more pressure that I’d like to see, I’m sure it’s pushing through the seats. Looks like you’ve got a few things to take care of but I’m sure with the genus’s on here you get it figured out I no time.

Jake
Click to expand...
Hi Jake. Bearing clearance was spot on. Prior to cam dieing, I had 60psi at idle. Cam was broken in long before it wiped out. It died shortly after I switched to synthetic oil. Don't know if that was the cause, but I am assuming that's why. I do know that after motor warms up at 180* is when oil psi drops to 5 at idle. Thinking maybe wiped cam bearings? The weird thing is motor runs strong for about 10 minutes. Only after warming up does it start acting weird.
 
yellow rose said:
If you had to grind on your rockers the geometry is wrong. Just an FYI.

Why is the fuel pressure so high? Is it a dead head system or a bypass system?
I use electric pumps because I thought it was cool. Plus the machine shop had numerous cams there where the fuel pump lobe had wiped out. So I thought I'd save myself the trouble. It could just be my psi gauge reading incorrectly (doubtful, but possible).

Your oil pressure issue is worse than the fuel pressure issue.

5 pounds of oil pressure at idle is just wrong. Why is the pressure so low?

You have some serious issues that need to be addressed...pronto.
Click to expand...
I don't know why oil psi is low. Drops after warm up. Bad pump? Wiped cam bearings?
Ground rockers because they are chinese and weren't clearanced for the large springs.
 
4spdragtop said:
Wiped cam....5 psi hot...cold exhaust. Like Jake said that doesnt sound good. If it was mine I would be tempted to pull it.
POS 340? I understand frustrations but that adjective might be saved for elsewhere(machinist/advisor etc...lol)
Also why battery in the trunk?
Click to expand...
 
Cold exhaust manifold runners tell me they are not making power. 12.5 psi on the fuel is way to high. Oil pressure was good before you lost a cam tells me your bearings have been scarred and you are loosing pressure there. It’s time to start over. Or send me your POS 340 and both of our lives will be better.
 
Are you saying my roller cam is bad? Battery is in trunk because I wanted the weight in back over right rear wheel. The previous cam was a flat tappet that died shortly after I changed to synthetic oil.
 
SGBARRACUDA said:
Cold exhaust manifold runners tell me they are not making power. 12.5 psi on the fuel is way to high. Oil pressure was good before you lost a cam tells me your bearings have been scarred and you are loosing pressure there. It’s time to start over. Or send me your POS 340 and both of our lives will be better.
Click to expand...
Car should have a 383 because that's what came in it. Get me a 383 and you can have the 340 with both x heads and the alluminum heads.
 
What weight of synthetic oil is in there now? And what weight of non-synthetic was being used when the oil pressure was higher? If the oil did not have adequate ZDDP, then that is probably what killed the prior cam lobes.

That fuel pressure may be the running problem. It runs OK when cold because the engine needs an enriched mixture when cold to run, but whan it warms up, then the extra rich mixture caused by the excess fuel pressure is making some cylinders misfire. It is like have a manual choke on all the time; it is right when cold, but then is wrong when warmed up.

But with an electric pump, you have to test it right. If you just pull the fuel line off the carb and plug it into a pressure gauge (dead-headed into the gauge) then electric pumps will tend to go high on their output. So you have to put a Tee into the line, near the carb, and then put the pressure gauge on the side port of the tee, and then idle the engine to get a valid pressure reading.
 
nm9stheham said:
What weight of synthetic oil is in there now? And what weight of non-synthetic was being used when the oil pressure was higher? If the oil did not have adequate ZDDP, then that is probably what killed the prior cam lobes.

That fuel pressure may be the running problem. It runs OK when cold because the engine needs an enriched mixture when cold to run, but whan it warms up, then the extra rich mixture caused by the excess fuel pressure is making some cylinders misfire. It is like have a manual choke on all the time; it is right when cold, but then is wrong when warmed up.

But with an electric pump, you have to test it right. If you just pull the fuel line off the carb and plug it into a pressure gauge (dead-headed into the gauge) then electric pumps will tend to go high on their output. So you have to put a Tee into the line, near the carb, and then put the pressure gauge on the side port of the tee, and then idle the engine to get a valid pressure reading.
Click to expand...
 
I switched back to convetional oil.
I will go out on a limb here and say that oil pressure doesn't drop until after warm up and motor is trying to stall. If I feather the throttle, the pressure will climb with increased rpm's. Only to about 20. 30 maybe 40 max when running hard.
 
Demonic said:
Your fuel pressure is way too high, as others said. Could have led to thin oil, which might contribute to low idle pressure. How do the plugs look? Post pics!
Click to expand...

I didnt catch it , 12 1/2 pounds fuel pressure with a carb or fuel inj ? For either one , it aint right !!~


Sum up to operator error !!
 
I will post a video of the car running and my fuel pressure gauge at 12.5 psi. I have adjusted it all the way out and no changes so fa .
 
famous bob said:
I didnt catch it , 12 1/2 pounds fuel pressure with a carb or fuel inj ? For either one , it aint right !!~
Electric jegs pump. Don't know if it is Holley red or blue equivalent hooked to 750 Holley carb.

Sum up to operator error !!
Click to expand...
 
VonCramp said:
I thought so too. Hooked up a new on . Same readings.
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At 12.5 pounds of pressure there isn’t a needle and seat package in this world that will shut the fuel off. If the pressure is that high, get the engine running and look into the carb, if fuel isn’t gushing out of the boosters and blowing out the vent tubes, your gauge is garbage.

Start with that so you have a answer for that. Unless you used a junk, new car synthetic, synthetic oil didn’t kill your cam.

If you did use some off the shelf, low grade oil then that’s why the cam failed. The base oil didn’t have a thing to do with it.
 
You don't need a electric pump. The mechanical would work just fine. By adding all the "racy" parts you are just shooting yourself in the foot so to speak. Your excessive fuel pressure could have thinned the oil, ruined your first cam (this one too) and trashed your bearings.
 
toolmanmike said:
You don't need a electric pump. The mechanical would work just fine. By adding all the "racy" parts you are just shooting yourself in the foot so to speak. Your excessive fuel pressure could have thinned the oil, ruined your first cam (this one too) and trashed your bearings.
Click to expand...

You are assuming his fuel pressure is that high. I’m beginning to doubt his number on fuel pressure because at that pressure it wouldn’t run at all for all the fuel blowing past the needle and seats.
 
toolmanmike said:
You don't need a electric pump. The mechanical would work just fine. By adding all the "racy" parts you are just shooting yourself in the foot so to speak. Your excessive fuel pressure could have thinned the oil, ruined your first cam (this one too) and trashed your bearings.
Click to expand...
I opted for electric because I had been shown bad cam fuel pump lobes on all makes of cams. Also, did you know there are only around 3 cam manufacturers in reality? The companies just add their own grind to them. Fuel is not pouring out and the oil is not thinned. Changed it yesterday and it still drops to 5 when motor is stalling
 
VonCramp said:
I opted for electric because I had been shown bad cam fuel pump lobes on all makes of cams. Also, did you know there are only around 3 cam manufacturers in reality? The companies just add their own grind to them. Fuel is not pouring out and the oil is not thinned. Changed it yesterday and it still drops to 5 when motor is stalling
Click to expand...


There are only 3 cam CORE manufacturers, not 3 cam companies.

Ok...so if there ain’t fuel blowing out the boosters and vents, your gauge is garbage. That’s all that can be. You can’t have that much fuel pressure and expect it to not push fuel out every hole it can find.

That still doesn’t address your oil pressure issues, which is going to require pulling the engine.


BTW, a small block Chrysler doesn’t have a fuel pump lobe on the cam. It uses a bolt on eccentric that bolts on in front of the cam gear.

FWIW, as a general rule, if the fuel pump bolts to the block it will have a lobe on the cam for the fuel pump. If the pump bolts to the timing cover, it will have a bolt on eccentric on the cam gear. If you remember that, you can walk up to most any Detroit engine and and be almost certain if it has a lobe on the cam or an eccentric.
 
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