Okay guys. My post is somewhat like the one four or five below from iowawebtowns. Vampiro and everyone else's suggestions have been great but my problem persists if not worse. I have new plugs, wires, diz cap is clean and good shape, new air & fuel filter, almost all new vac lines. Have checked timing and I think it is set at 9 or 10 ATDC?? Also used a vaccum gauge to do some rough tests, I thought I looked good. Tonight rolling along bout' 45 or so, she started acting up again. Mild to moderate hesitation, (I could swear I hear a spitting type sound from under the hood), not consistent though. On again off again. Seems only to do it once warmed up and doing regular speeds of 35\40 or more. She made a sound something like a acorn hitting the metal (only did it once) I was thinking the carb backfired?? After that she seemed to run a little rougher and started to lose power. I eased her home, can't find any leaks, no gauges went crazy, oil pressure is good. At idle I can't tell much, I think it may be missing a little now, I am not sure. My PCV hose is actually heater core hose and it seemed to be sucking itself closed due to the way I have it just laying in there. Would this pose a threat? I think the valve is good (it rattles), and I think it was still getting some flow even though the hose was a little compressed. What should I start with guys? I have learned a lot but I have a long way to go, and it is killing me that I can't get this truck going strong. Since I'm not smoking or dripping is that a relativly good sign?? Could anyone try and get back to me by Saturday, I will be off and can look at her then. Thanks so much, Blair

 

[updated:LAST EDITED ON 16-May-02 AT 09:22 PM (EST)]First change the pcv hose that does'nt help heater hose is to soft thats why its collapsing. Your post says you have a holley carburator and from what your saying you might have a power valve bad i would focus on your carb first. Check your plugs and see if there black (running rich) holleys are notorious for the metering block going bad and or blowing power valves and the other thing to think about is the fuel pump it might be starting to go bad.


Wiz

 

Your post says your timing is 9-10 AFTER TDC. Should be BEFORE TDC. Somewhere in the neighborhood of 10-14 degrees.

-Scouder

 

I'd bet 20 bucks to a donut that your timing chain is stretched. When my chain went out I checked my timing four times and I'll swear it was within spec each time. My truck was acting just like yours and after spending a few hundered on everything from a new brain box, distributor, coil, cap, wires, plugs, fuel pump, and carb I finally pulled the timing cover off. I spent all that money because thats how positive I was the timing was okay. I've been racing at the digs for over 20 years now and I have never seen a timing chain act like that before. That is until I talked to others that own a Ford (sorry but I always had Dodge or Chevy because my Dad had a Ford). It seems that these factory chains will stretch a long ways before they finally give. Unlike a Chevy/Dodge that will break a tooth or jump without any warning at all. When I pulled mine a part I could rock the crank 5-7* without moving the cam.

 

I had a similar problem with my old 360. The thing would run like a dream, and then it would spit and sputter and lose all power..almost die. I'd then hit a bump and it would be back to running well again.
Sometimes it mysteriously cured itself. Ended up my distributor shaft/assembly was shot..a lot of play in it and I saw some metal shavings down around the mechanical vacuum advance. replaced it with a rebuilt and never had the problem. Just an idea. Hope it helps.
DutchmanAZ

 

I had the same problem with a 3.8L V6. Was the timing chain also.

>I'd bet 20 bucks to a donut that your timing chain is
>stretched. When my chain went out I checked my timing four
>times and I'll swear it was within spec each time. My truck
>was acting just like yours and after spending a few hundered
>on everything from a new brain box, distributor, coil, cap,
>wires, plugs, fuel pump, and carb I finally pulled the
>timing cover off. I spent all that money because thats how
>positive I was the timing was okay. I've been racing at the
>digs for over 20 years now and I have never seen a timing
>chain act like that before. That is until I talked to others
>that own a Ford (sorry but I always had Dodge or Chevy
>because my Dad had a Ford). It seems that these factory
>chains will stretch a long ways before they finally give.
>Unlike a Chevy/Dodge that will break a tooth or jump without
>any warning at all. When I pulled mine a part I could rock
>the crank 5-7* without moving the cam.

 

Hey thanks for the replies. A question I have is this. When I replaced my Crankshaft seal I glanced at the timing gears to see if I had chipped teeth or anything like that. In all honesty I wouldn't know good from bad yet, but I remember looking at my timing chain (looking at engine from front now) and the chain seemed fairly tight from the camshaft down to the crankshaft along the left side, but the right side had probably 1/4" to 1/2" of sag or give in it. Should it be tight consisently all the way around?? Would this affect the way she is running? I was thinking this problem might be fuel system related, but I have cleaned my carb and I guess its in proper working order. (Not enough experience to know yet) You guys think I should put on a new chain? No big deal cept I was just in there few weeks back. For the guys that are saying check carb, would this be in the manuel for the Holleys, if so I have one, I'm thinking why not go ahead and pull it for a real good cleaning. At least less stuff to trouble shoot. Thank you guys, keep the ideas coming. Blair

 

Replace the timing chain. It should be tight on both sides. When the engine speeds up and slows down the play will go to the other side, changing the timing.

Me_Bad_Dog(No Email Addresses In Posts!)
74 F-250 4X4
In process of rebuilding
460cid
np435
np205 devorced
looking for dana 60 open knockle front

 

It's the chain. Mine had about the same play, maybe a little less in it. Be sure when you replace it you use a NON-factory (read NON-Ford) chain assembly. The factory crank gear has a retard built into it that robs the engine of low-end torque. Use a good 3-way double roller timing set from companies such has Crane or Comp Cams, and set it "straight" up (that will be the keyway in the middle of the 3). The complete set should run you around 30-35 bucks. I got mine for 19 (racers net)

 

Hmmmm....If the timing chain doesn't solve your problems I'm wondering about that new fuel filter? You say it's new, but have you replaced or messed with any metal or rubber fuel lines after replacing the filter? If so, I would bet that another new fuel filter would help. Long story short("She's Givin' Me Trouble Again, Part II post) I replaced my Old fuel filter and then a lot of fuel related tubing and hoses and in the process knocked some crud loose in the old metal lines that then plugged my New fuel filter. I cut it open with a tubing cutter and unfolded the paper pleates only to find a lot of silt and crud blocking the fuel delivery. It gave me some of the same symptoms you've described except that acorn on metal sound. So after replacing and blowing out the fuel lines and dropping and cleaning out my tank and then putting a second new fuel filter on my problems were fixed. It couldn't hurt to spend a couple bucks and minutes on a new filter, cut the old new filter open and check it out before doing a lot of work on the timing chain or carb.

Anyway, that's my two cents. Hope it helps.

 

[updated:LAST EDITED ON 20-May-02 AT 12:37 PM (EST)]Onceagain thanks to everyone for repliying. I got it apart Sunday after work, have to get new chain and gears, it rained Sat. morning and delayed me, other than non-factory setup do I need to look at anything else? You guys have been more than helpful and I thank you for it. Last thing, someone feel like putting in idiot terms on how to make final timing adjustments? Having never done it before, I would really like to have someone from here give me a play by play. :-X11 Once again, thanks for all input, I'll post some results of new timing setup later this week when I get it installed. Blair


Thanks for suggestion cigar, you may be right I'll have to lokk into another filter. There're cheap, my lines are relativly new, but for a while I've thought maybe my tank is contaminated as put in other posts. Thanks again, Ciao.

 

All/78,
If the timing chain is "stretched", why does it run well when its cold? You said you had a 360, didn't you? You said , "you replaced the cam seal." Where is the cam seal on a 360? I'll assume you were talking about the timing chain cover gasket? Were your gears solid metal or were they brown plastic,"nylon". Play on one side of the set is normal. A 1/2 inch is accessive. Nylon gear sets are a thing of the past but, if you've got them you've probally got timing chain problems.
Secondly, I am not getting a timing chain "vibe" here. An intermittent timing failure at temperature tells me coil or stator pickup in distributor. I wish you luck.
KingFisher

 

Another question, sorry for the long posts. When replaceing gears and chain, when I rotate crank and cam to line up, do I line up the raised "keyway" or the lowered "keyway that had the key in it on the crank with the little triangular mark on the cam? I would assume that I rotate the motor with old gears and chain on? Not doing this til Thursday cause I'm busy. Any tips are certainly appreciated. Thanks, Thanks & thanks again. BLT

 

Turn the crank until the dot on the cam gear is facing down and the dot on the crank gear is facing up to the cam dot. Besure that these dots are aligned BEFORE you remove the old chain and gears. Use a straight edge such as a metal ruler or a credit card (my sears card worked great) to be sure you have the dots in line with each other. If you can't see the dots use some brake cleaner or wd-40 to clean the gears. Then use a highliter such as a yellow grease stick (or white house paint apllied by using a rag and wiping it over the gear) to help you find there locations.

When you install the new chain I recommend that you install a good NON-Factory double roller timing chain. I would get an Edelbrock, Crane Cams or Comp Cams gear set with the 3 keyed crank gear and install it on the middle "straight up" keyway (has you look at the gear the keyway will be directly bellow the tooth and not off to oneside). This will put the cam back on its "straight up" timing and improve your bottom end torque.