302 valve adj. problem
Thread Starter
|
Elder User
Joined: Mar 2004
Posts: 652
Likes: 0
302 valve adj. problem
I have built a 96 5.0 to replace 69 302. I used ford racing hydraulic roller cam. .498 lift, 284 duration, H.O. Firing order. I used GT40-p heads, 240 lb springs, and ford racing hydraulic roller lifters. Melling H.V. oil pump. 40 lbs pressure at idle, about 70 pounds at 5000 rpm. I replaced ped. style mounting with 3/8 in. studs. Used 1.6 ratio adjustable roller rockers.
I can not get the vales adjusted. It is kind of embarrasing because I have been adjusting solid tappet roller cams for years with no problem. If I adjust the valves tight enough so they do not tick cold, the engine starts skipping terrible when It warms up. If I adjust the skip out, the engine, the tick is back when I crank it cold. I tried adjusting the engine the way the service manual calls for. Bleed down lifters and set .14 gap. That was a mistake, the engine cut off as soon as it cam up to oil pressure. Does anyone have any suggestions, If not, I am going to a solid tappet roller cam.
I can not get the vales adjusted. It is kind of embarrasing because I have been adjusting solid tappet roller cams for years with no problem. If I adjust the valves tight enough so they do not tick cold, the engine starts skipping terrible when It warms up. If I adjust the skip out, the engine, the tick is back when I crank it cold. I tried adjusting the engine the way the service manual calls for. Bleed down lifters and set .14 gap. That was a mistake, the engine cut off as soon as it cam up to oil pressure. Does anyone have any suggestions, If not, I am going to a solid tappet roller cam.
Elder User
Joined: Apr 2003
Posts: 627
Likes: 1
what I think you may be hearing is valve noise not lifter noise, due to the fast ramps on the cam the valves clatter when they close , no cure I know of. Adjust the valves with the engine running (messy) by loosening until they tick tightening until they stop and then a further 1/3-1/2 turn each time the engine will stumble and try to quit but should smooth out within a few seconds, just repeat for each and if the noise reoccurs it's the valves not the lifters, if they are only noisy when on new cold startup your lifters are bleeding down. good luck
Posting Guru
Joined: Jul 2003
Posts: 1,486
Likes: 0
From: Independence, MO
try making shure the piston is on comprsion stroke back off the rocker till you can feel the slack in the pushrod, the slightly tight the rocker till the slack just barly goes away, and i dont mean colapsing the plunger in the lifter, just untill there no slack between the plunger and the rocker, then tighten the nut 1/2 turn and tighten the poly lock and it should be fine. of course repeat for each cylinder. DW
Thread Starter
|
Elder User
Joined: Mar 2004
Posts: 652
Likes: 0
thanks for the advice. I will definitely try the adjustments befor I do anything drastic. Today, I talked with a professional engine builder who builds lots of performance street engines and race engines. He says the problem is the Ford Racing hydraulic roller lifers are junk. He says the oil pressure of the race pump is excessively popping up the lifters when the engine warms up and the oil viscosity rises. He said try SAE 30 instead of 10-40. He said if that doesn't work change either the oil pump or the lifters. That just doesn't sound right to me. What do you think?
Posting Guru
Joined: Jul 2003
Posts: 1,486
Likes: 0
From: Independence, MO
i dont know sounds kida weird to me i'd try the adjustment again, cuzin is running the x-303 cam in his maverick with no problems at all, if you go to my web site and click (my favorite places) then click (cuzin mikes place) you can see his maverick. Good Luck let me know what you come up with. DW
Elder User
Joined: Dec 2003
Posts: 655
Likes: 0
From: Miami
Out of curosity, did you check pushrod length? Did you check the clearance on the bottom of the rocker to the stud, .030 minimum required. I just did a re-build and had to go to longer pushrods in order to get the clearance and proper valve train geometry. EXTREMELY important when going with adjustable roller rockers. Everybody blast's them, but that's because they are usaully not installed properly. I bought Comp Cam's parts installed them and new something was wrong, but did not no what. Cust. service did not understand why I was having problem's, probably thought I was an idiot. Absolutly no instructions came with there parts. Switched to Crane pedestal rocker mount kit and the instructions told me everything I was experiecing and how to fix it and set the valve train geometry. Go to this web site www.network54.com/forum/119417 and there is a link to a question 351 heads on a 289. The link tells you how to check pushrod length if you think that is a problem.
Al
Al
Thread
Thread Starter
Forum
Replies
Last Post
Jeff92f150
Small Block V8 (221, 260, 289, 5.0/302, 5.8/351W)
21
Jan 28, 2008 12:38 PM
FEina52F1
FE & FT Big Block V8 (332, 352, 360, 390, 406, 410, 427, 428)
7
Feb 11, 2002 10:06 AM
