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5.4 pi heads and intake on my 98 f150 4.6

 
  #1  
Old 06-28-2019, 02:43 PM
Joseph Gamble
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5.4 pi heads and intake on my 98 f150 4.6

Got the swap done .new timing components .lapped and reseated valves all new gaskets. .belts.pumps.plugs.wires..wxcitex to turn key and now I have good crank no start.got good spark .take shrader valve out and she sprays fuel ..did set a code .it pertains to fuel pump relay .inertia switch .short causing pump to stay on ..think I fixed that so I erased code . basically went through a check list and found nothing wrong ..I'm stumped .took my time everything is correct .one thing I'm not sure of is the cams .after reseating them I placed the cams on the heads close to where they should be to time and let the cam lobes move the valves to where they moved .set one on tdc .dropped all pistons below deck and cominced to installation of everything being very careful not to move crank ...as cautious as I was I figured she would fire up... Do I need a programmer or something ?please help
 
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Old 06-28-2019, 03:44 PM
freak007
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Most codes won't set without starting....

Turn the ignition on and wait 5 seconds before cranking.

Have you run a compression test?
Checked actual fuel pressure?
Measure the voltage across the battery while cranking.
 
  #3  
Old 06-29-2019, 04:27 AM
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Was the Crankshaft Position Sensor ever disconnected during this repair?
 
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Old 07-01-2019, 11:56 PM
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Now that you ask I really can't recall .would it have made a difference
 
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Old 07-02-2019, 03:57 AM
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Originally Posted by Joseph Gamble View Post
Now that you ask I really can't recall .would it have made a difference
It would only matter if its no longer connected or otherwise "talking" to the PCM. Simply disconnecting and re-connecting it wouldn't cause an issue.

You might double check that connection and wiring leading away from the CPS---some damage to it could have happened while your other work was in process.
 
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Old 07-02-2019, 11:51 AM
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I just finished the PI swap myself. The only comment you made that is concerning, is the timing. I think if the Crank Position sensor was unplugged you would not have spark.

I would check compression on all 8 to see if there are any cylinders that won't pump up, or if there is any great difference. That should show if your timing is messed up or if there is a problem with your head gaskets. Did you replace intake as well? If you did not, I would double check you used the right head gasket and that it is properly positioned.

I did heads, intake, and cams. Fired right up. But I installed everything as part of an engine out rebuild, so I was able to ensure the cams were right before I covered everything up.

Hope you figure it out. It makes a big difference.

Joel
 
  #7  
Old 07-02-2019, 06:00 PM
Joseph Gamble
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backfiring repeatively

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1998 4.6 4x4 backfiring repeatively

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#1
Joseph Gamble , 05-15-2019 09:58 PM
I bought truck cheap .previous owner stated they thought it jumped time they jeard a loud pop then truck ran terrible..towed it home and started tearing into it .found that the lower plenum..what I suspected was blown apart (in pieces)by the loud pop they heard .backfire in intake I presume ..i went ahead and tore down everything except for removing the heads ...replaced all aspects of timing along with oil pump water pump alternator and so on..watched hrs of videos and read everythi g I could find on internet aboit timing my 4.6...now after putting it back together .start up it purrs no problems .put it in gear and take off and it backfires repeatively .the faster I go the faster it pops..slow down to an idle and it purrs again..im thinking either stuck valve or my cam timing is off..also I put shorty headers on and straight piped the exhaust .no cats..ran a compression check and cylinder 7 is lower than the rest by about 25psi. If I pull the covers is there a way to check for a stuck valve ? This is the first time ive ever attempted wrenching on a motor aside from basic starter or oil change . any advice would be helpful
#2
Joseph Gamble , 05-16-2019 01:36 AM
Repeatitive backfiring
Joseph Gamble , Today 05:23 PM
Bought my 98 4x4 4.6 with a blown out lower intake plenum .previous owner said he heard a loud pop then it ran terrible.he thinks it jumped time..i towed it home and tore into it .i found the lower plenum to be in pieces .bought a used one and proceeded to tear down all the way to the heads without removing them..i replaced every aspect of the timing ..chains .guides.tensioners.crank sprocket.did not change cam sprockets because my engine is a windsor and I read they are pressed on..oil pump.water pump .alternator .everything new.upon opening up the timimg cover I found nothing out of place .chain had what appeared to me as a lil slack but nothing out the ordinary..so I followedbthe step by step instructions ans replaced my parts ..i watched and read hrs amoungst hrs of info on how to do so and was very careful...now truck fires rite up and purrs .once I take off it backfire repeatively. the faster I go the faster the backfire .i beleive its a combo of intake and exhaust backfires..i also put shorty headers on and straight piped exhaust..no cats..im thinking I have a stuck valve or my cam timing is off.i did not use any locking tools .but again was very careful...is ther a way to check for a stuck valve by taking off valve/cam covers ?? My next step is to buy the degree wheel kit.pull the motor. put on a stand and start from scratch retiming everything .id like to avoid this if possible so any suggestions will be greatly appreciated ..not a mechanic this is my first endeavour aside from a simple starter or oil change..motor has 187.000 on it and I did change could plugs and wires also..thanks also truck is a manual.






#3
alloro , 05-16-2019 02:31 PM
When it jumped time it could've bent a valve. You're going to have to do a leak down or compression test on each cylinder to find out.
#4
Joseph Gamble , 05-17-2019 12:29 AM
I did compression test cylinder 7 is 30 psi less than other cylinders ..is there a way to visually check for bent valve with cover off..?and do you have to pull head id valve is bent? Should I replace all the valves or just get used windsor heads ?I know where running motor and trans out of crown vic for really cheap.it is windsor same year also.

#5
Bluegrass 7 , 05-17-2019 05:16 AM
Bring that cylinder up on compression stroke so the valves are closed.
Apply air pressure though the spark plug hole.
Listen to the intake tract for the air escape noise.
If you hear it there, obvious the intake valve is leaking for whatever reason when the cylinder should be sealed..
You may have to hold the crank from turning if the cylinder seals and there is no leak.
To know if the cylinder it supposed to be sealed, look at the valves for that cylinder. Both will have the rocker on the cam lobe non lift areas of the lobes so the valves are closed.
Good luck.
#6
alloro , 05-17-2019 02:41 PM
Quote:Originally Posted by Joseph Gamble
I did compression test cylinder 7 is 30 psi less than other cylinders ..is there a way to visually check for bent valve with cover off..?and do you have to pull head id valve is bent?
Definitely bent a valve and the only way to see it is to remove the head. Not that it really matters if it's the intake or exhaust because in either case the head has to come off.
#7
Joseph Gamble , 05-17-2019 04:16 PM
Ok so I'm going to pull the motor and tear it down .remove the heads .can I replace just the bent valve or do I have to replace all on that side .and in assuming ill be able to tell which is bent upon removal of the head......another question .should I remove both heads just to give everything a good cleaning and inspect .someone metioned to me something about since im there I shoulx re_seat all the valves .is this necessary..what would you do??
#8
alloro , 05-18-2019 04:18 PM
Any valves you replace will have to be lapped, at the very least. If you don't at least lap them they will not seal. As far as pulling both heads, for me if I'm that far into a project I go all in. If it were me and I had both heads off I'd actually bring both heads to a shop and have a valve job done.

#9
Joseph Gamble , 05-18-2019 04:35 PM
So how much do u think a valve job costs in on a limited budget .i do know of a windsor same year that runs w tranny out of a crown Vic..video of it running .i can get for 150.could I pull headsboff it and use then over time slowly rebuild the blocked my heads .and have a new motor when done ..if I do this I could maybe not pull my engine just tear downnand swap heads and use my intake .should save time and money .sale the tranny oit the c
#10
Joseph Gamble , 05-18-2019 05:32 PM
Ok so im going to get the 150 windsor that runs .has 200,000 plus on it .and has the trans .im thinking kust put those heads on mine and degree the cams while retiming the whole thing...this will get me on the road ..sell the trans and rebuild from the ground up the 4.6 block and get some pi heads .have them redone maybe look for wrecked cobra .or something .take my time and wen done ill have a beast of a f150 .ill upgrade my suspension a lil.and use the whole experience as a learning one ..ive already learned a ton being this is my first motor ive gotten this evolved and have had people tell me u was nuts for tackling a modular with no experience ..looked at a 78 chevy engine a buddy got and help him tear it down and to me after my 4.6 ...it looked so under engineered ..not knocking it but was alot simplar...have had people including my woman of 14 years I should just trade my truck in on a newer one .well ive about turned every bolt on my f150 and to me for the money I wouldnt trade it in for anything I actually feel as if its a partbof me now and im gonna keep steamin forward till shes absolutely perfect..250 bucks and 100 man hrs later ..that truck is mine.......ill keep posting my progress and thanks to everyone who gave there opinions and advice .couldnt have done with out you guys👍👍👍
#11
alloro , 05-19-2019 03:39 PM
Quote:Originally Posted by Joseph Gamble
So how much do u think a valve job costs in on a limited budget
The cost varies between shops and areas of the country. My best answer is to ask a couple of local shops.
#12
Joseph Gamble , Today 10:39 PM
Okay ..found some 5.4 pi heads. And intake ..tore motor down and followed all instructions .motor would turn over bit not start or hit so I checked spark.found my fuel pump was weak .replaced the next day and went to crank and sounded completely different .found coolant in oil.so I ended up finding somehow I reversed the intake manifold gaskets ..so I fixed and drained the oil cahnged filter .still wen I crank it sounds almost like the Bendix on starter is just spinning ..this is while I'm checking compression w all plugs out .I dropped oil pan and inspected underside and every thing looks fine .wen I turn over by hand it makes a screeching sound like no lube but stopped wen I put new oil in..I'm not understanding it's almost like the starter isn't strong enough now to turn the crank .ive only attempted compression check on one cylinder and it's like 4o..I lapped valves my self .someone mention did I pop them .?? No idea wat this means .I'd hate to have to pull heads again..help please
 
  #8  
Old 07-02-2019, 06:01 PM
Joseph Gamble
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1998 4.6 4x4 backfiring repeatively

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#1
Joseph Gamble , 05-15-2019 09:58 PM
I bought truck cheap .previous owner stated they thought it jumped time they jeard a loud pop then truck ran terrible..towed it home and started tearing into it .found that the lower plenum..what I suspected was blown apart (in pieces)by the loud pop they heard .backfire in intake I presume ..i went ahead and tore down everything except for removing the heads ...replaced all aspects of timing along with oil pump water pump alternator and so on..watched hrs of videos and read everythi g I could find on internet aboit timing my 4.6...now after putting it back together .start up it purrs no problems .put it in gear and take off and it backfires repeatively .the faster I go the faster it pops..slow down to an idle and it purrs again..im thinking either stuck valve or my cam timing is off..also I put shorty headers on and straight piped the exhaust .no cats..ran a compression check and cylinder 7 is lower than the rest by about 25psi. If I pull the covers is there a way to check for a stuck valve ? This is the first time ive ever attempted wrenching on a motor aside from basic starter or oil change . any advice would be helpful
#2
Joseph Gamble , 05-16-2019 01:36 AM
Repeatitive backfiring
Joseph Gamble , Today 05:23 PM
Bought my 98 4x4 4.6 with a blown out lower intake plenum .previous owner said he heard a loud pop then it ran terrible.he thinks it jumped time..i towed it home and tore into it .i found the lower plenum to be in pieces .bought a used one and proceeded to tear down all the way to the heads without removing them..i replaced every aspect of the timing ..chains .guides.tensioners.crank sprocket.did not change cam sprockets because my engine is a windsor and I read they are pressed on..oil pump.water pump .alternator .everything new.upon opening up the timimg cover I found nothing out of place .chain had what appeared to me as a lil slack but nothing out the ordinary..so I followedbthe step by step instructions ans replaced my parts ..i watched and read hrs amoungst hrs of info on how to do so and was very careful...now truck fires rite up and purrs .once I take off it backfire repeatively. the faster I go the faster the backfire .i beleive its a combo of intake and exhaust backfires..i also put shorty headers on and straight piped exhaust..no cats..im thinking I have a stuck valve or my cam timing is off.i did not use any locking tools .but again was very careful...is ther a way to check for a stuck valve by taking off valve/cam covers ?? My next step is to buy the degree wheel kit.pull the motor. put on a stand and start from scratch retiming everything .id like to avoid this if possible so any suggestions will be greatly appreciated ..not a mechanic this is my first endeavour aside from a simple starter or oil change..motor has 187.000 on it and I did change could plugs and wires also..thanks also truck is a manual.






#3
alloro , 05-16-2019 02:31 PM
When it jumped time it could've bent a valve. You're going to have to do a leak down or compression test on each cylinder to find out.
#4
Joseph Gamble , 05-17-2019 12:29 AM
I did compression test cylinder 7 is 30 psi less than other cylinders ..is there a way to visually check for bent valve with cover off..?and do you have to pull head id valve is bent? Should I replace all the valves or just get used windsor heads ?I know where running motor and trans out of crown vic for really cheap.it is windsor same year also.

#5
Bluegrass 7 , 05-17-2019 05:16 AM
Bring that cylinder up on compression stroke so the valves are closed.
Apply air pressure though the spark plug hole.
Listen to the intake tract for the air escape noise.
If you hear it there, obvious the intake valve is leaking for whatever reason when the cylinder should be sealed..
You may have to hold the crank from turning if the cylinder seals and there is no leak.
To know if the cylinder it supposed to be sealed, look at the valves for that cylinder. Both will have the rocker on the cam lobe non lift areas of the lobes so the valves are closed.
Good luck.
#6
alloro , 05-17-2019 02:41 PM
Quote:Originally Posted by Joseph Gamble
I did compression test cylinder 7 is 30 psi less than other cylinders ..is there a way to visually check for bent valve with cover off..?and do you have to pull head id valve is bent?
Definitely bent a valve and the only way to see it is to remove the head. Not that it really matters if it's the intake or exhaust because in either case the head has to come off.
#7
Joseph Gamble , 05-17-2019 04:16 PM
Ok so I'm going to pull the motor and tear it down .remove the heads .can I replace just the bent valve or do I have to replace all on that side .and in assuming ill be able to tell which is bent upon removal of the head......another question .should I remove both heads just to give everything a good cleaning and inspect .someone metioned to me something about since im there I shoulx re_seat all the valves .is this necessary..what would you do??
#8
alloro , 05-18-2019 04:18 PM
Any valves you replace will have to be lapped, at the very least. If you don't at least lap them they will not seal. As far as pulling both heads, for me if I'm that far into a project I go all in. If it were me and I had both heads off I'd actually bring both heads to a shop and have a valve job done.

#9
Joseph Gamble , 05-18-2019 04:35 PM
So how much do u think a valve job costs in on a limited budget .i do know of a windsor same year that runs w tranny out of a crown Vic..video of it running .i can get for 150.could I pull headsboff it and use then over time slowly rebuild the blocked my heads .and have a new motor when done ..if I do this I could maybe not pull my engine just tear downnand swap heads and use my intake .should save time and money .sale the tranny oit the c
#10
Joseph Gamble , 05-18-2019 05:32 PM
Ok so im going to get the 150 windsor that runs .has 200,000 plus on it .and has the trans .im thinking kust put those heads on mine and degree the cams while retiming the whole thing...this will get me on the road ..sell the trans and rebuild from the ground up the 4.6 block and get some pi heads .have them redone maybe look for wrecked cobra .or something .take my time and wen done ill have a beast of a f150 .ill upgrade my suspension a lil.and use the whole experience as a learning one ..ive already learned a ton being this is my first motor ive gotten this evolved and have had people tell me u was nuts for tackling a modular with no experience ..looked at a 78 chevy engine a buddy got and help him tear it down and to me after my 4.6 ...it looked so under engineered ..not knocking it but was alot simplar...have had people including my woman of 14 years I should just trade my truck in on a newer one .well ive about turned every bolt on my f150 and to me for the money I wouldnt trade it in for anything I actually feel as if its a partbof me now and im gonna keep steamin forward till shes absolutely perfect..250 bucks and 100 man hrs later ..that truck is mine.......ill keep posting my progress and thanks to everyone who gave there opinions and advice .couldnt have done with out you guys👍👍👍
#11
alloro , 05-19-2019 03:39 PM
Quote:Originally Posted by Joseph Gamble
So how much do u think a valve job costs in on a limited budget
The cost varies between shops and areas of the country. My best answer is to ask a couple of local shops.
#12
Joseph Gamble , Today 10:39 PM
Okay ..found some 5.4 pi heads. And intake ..tore motor down and followed all instructions .motor would turn over bit not start or hit so I checked spark.found my fuel pump was weak .replaced the next day and went to crank and sounded completely different .found coolant in oil.so I ended up finding somehow I reversed the intake manifold gaskets ..so I fixed and drained the oil cahnged filter .still wen I crank it sounds almost like the Bendix on starter is just spinning ..this is while I'm checking compression w all plugs out .I dropped oil pan and inspected underside and every thing looks fine .wen I turn over by hand it makes a screeching sound like no lube but stopped wen I put new oil in..I'm not understanding it's almost like the starter isn't strong enough now to turn the crank .ive only attempted compression check on one cylinder and it's like 4o..I lapped valves my self .someone mention did I pop them .?? No idea wat this means .I'd hate to have to pull heads again..help please
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  #9  
Old 07-02-2019, 06:03 PM
Joseph Gamble
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Originally Posted by Joseph Gamble View Post
Okay ..found some 5.4 pi heads. And intake ..tore motor down and followed all instructions .motor would turn over bit not start or hit so I checked spark.found my fuel pump was weak .replaced the next day and went to crank and sounded completely different .found coolant in oil.so I ended up finding somehow I reversed the intake manifold gaskets ..so I fixed and drained the oil cahnged filter .still wen I crank it sounds almost like the Bendix on starter is just spinning ..this is while I'm checking compression w all plugs out .I dropped oil pan and inspected underside and every thing looks fine .wen I turn over by hand it makes a screeching sound like no lube but stopped wen I put new oil in..I'm not understanding it's almost like the starter isn't strong enough now to turn the crank .ive only attempted compression check on one cylinder and it's like 4o..I lapped valves my self .someone mention did I pop them .?? No idea wat this means .I'd hate to have to pull heads again..help please
Guess I'll pull valve covers and have a look at
 

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