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Topic: Failed 5.0L Motor... (Read 2153 times) previous topic - next topic

Failed 5.0L Motor...

Well, since I finally got around to pulling the motor out of my TC I decided it would be nice to start a thread about it.  With PICS!

Anyway, about a month ago she started to make a noise and backfire through the carb.  I traced it down to a sticking valve.  So i pulled the heads, and everything was "ok". 

Today I pulled the motor to further troubleshoot.  Turns out the  lifter was sticking and that caused my cam to fail.  I do not plan on re-using this block.  However I was wondering what I could do about re-using the heads.  They are E7's.  The valves arn't damaged or anything, but I was worried about the valve guides being hurt.  Any suggestions?

Here are the pics.
84 TC 302 -5.0L/t5/7.5 locking rear and a 3.45 gear, Edelbrock Intake, Aluminum Heads, Edlebrock 65mm Throttlebody, Edlebrock Cam, 24lb injectors & MAS Air Sensor calibrated via chip,  BBK headers, Catback H pipe, Magnaflow lers :evilgrin:
:pics-stfu:

 Project Thread with pics

Failed 5.0L Motor...

Reply #1
And here are the pics of the cam and lifter.
84 TC 302 -5.0L/t5/7.5 locking rear and a 3.45 gear, Edelbrock Intake, Aluminum Heads, Edlebrock 65mm Throttlebody, Edlebrock Cam, 24lb injectors & MAS Air Sensor calibrated via chip,  BBK headers, Catback H pipe, Magnaflow lers :evilgrin:
:pics-stfu:

 Project Thread with pics

Failed 5.0L Motor...

Reply #2
A valve job should cost about 75-100, guides arent that bad to put in. then you will have fresh heads.
What happened run out of oil or pressure?
Old Grey Cat to this.88 Cat, 5.0 HO, CW mounts, mass air, CI custom cam, afr165's, Tmoss worked cobra intake, BBK shorty's,off road h pipe, magnaflow ex. T-5,spec stage 2 clutch, 8.8 373 TC trac loc, che ajustables with bullits on the rear. 11" brakes up front. +

Failed 5.0L Motor...

Reply #3
Pressure was the root cause.  My next setup will have an oil pressure gauge inside the car and not just under the hood.
84 TC 302 -5.0L/t5/7.5 locking rear and a 3.45 gear, Edelbrock Intake, Aluminum Heads, Edlebrock 65mm Throttlebody, Edlebrock Cam, 24lb injectors & MAS Air Sensor calibrated via chip,  BBK headers, Catback H pipe, Magnaflow lers :evilgrin:
:pics-stfu:

 Project Thread with pics

Failed 5.0L Motor...

Reply #4
That thing ran?  There's pretty much no lobe left.

Failed 5.0L Motor...

Reply #5
Quote from: blu84302;253020
Pressure was the root cause.  My next setup will have an oil pressure gauge inside the car and not just under the hood.


I doubt that, about every thing else will fail from low oil pressure, before the cam...

Failed 5.0L Motor...

Reply #6
Do you think it's possible that the valve stuck first, then caused the lifter to stick and then damage the cam?

See that's why I'm not sure about re-using the e7's.
84 TC 302 -5.0L/t5/7.5 locking rear and a 3.45 gear, Edelbrock Intake, Aluminum Heads, Edlebrock 65mm Throttlebody, Edlebrock Cam, 24lb injectors & MAS Air Sensor calibrated via chip,  BBK headers, Catback H pipe, Magnaflow lers :evilgrin:
:pics-stfu:

 Project Thread with pics

Failed 5.0L Motor...

Reply #7
That's pretty much what I was thinking: Did you rev it too high and bend a valve? Backfiring through the carb would indicate a valve that wasn't closing, not one that wasn't opening. I'd pull that valve out and check it for being bent. If it's really bent you might have difficulty getting it out...
2015 Mustang GT Premium - 5.0, 6-speed, Guard Green - too much awesome for one car

1988 5.0 Thunderbird :birdsmily: SOLD SEPT 11 2010: TC front clip/hood ♣ Body & paint completed Oct 2007 ♣ 3.55 TC rear end and front brakes ♣ TC interior ♣ CHE rear control arms (adjustable lowers) ♣ 2001 Bullitt springs ♣ Energy suspension poly busings ♣ Kenne Brown subframe connectors ♣ CWE engine mounts ♣ Thundercat sequential turn signals ♣ Explorer overhead console (temp/compass display) ♣ 2.25" off-road dual exhaust ♣ T-5 transmission swap completed Jan 2009 ♣

Failed 5.0L Motor...

Reply #8
The valve is out.  I ran it across a countertop and it didn't wobble.  So I'm going to say it wasn't bent.
84 TC 302 -5.0L/t5/7.5 locking rear and a 3.45 gear, Edelbrock Intake, Aluminum Heads, Edlebrock 65mm Throttlebody, Edlebrock Cam, 24lb injectors & MAS Air Sensor calibrated via chip,  BBK headers, Catback H pipe, Magnaflow lers :evilgrin:
:pics-stfu:

 Project Thread with pics

Failed 5.0L Motor...

Reply #9
Time to go roller anyway.
'88 Sport--T-5,MGW shifter,Trick Flow R intake,Ed Curtis cam,Trick Flow heads,Scorpion rockers,75mm Accufab t-body,3G,mini starter,Taurus fan,BBK long tube headers,O/R H-Pipe, Flowamaster Super 44's, deep and deeper Cobra R wheels, Mass Air and 24's,8.8 with 3.73's,140 mph speedo,Mach 1 chin spoiler,SN-95 springs,CHE control arms,aluminum drive shaft and a lot more..

Failed 5.0L Motor...

Reply #10
Roller... Meh.

I was thinking 460 redneck tire smoking machine.  But that's not in my budget.
84 TC 302 -5.0L/t5/7.5 locking rear and a 3.45 gear, Edelbrock Intake, Aluminum Heads, Edlebrock 65mm Throttlebody, Edlebrock Cam, 24lb injectors & MAS Air Sensor calibrated via chip,  BBK headers, Catback H pipe, Magnaflow lers :evilgrin:
:pics-stfu:

 Project Thread with pics

 

Failed 5.0L Motor...

Reply #11
I feel your pain! I was driving along last March and my engine(83 3.8l Carbed) started running like , you know,dropping a cylinder or something, I figured it was bad gas since the tank was almost empty. I hit the freeway headed home and less than a minute in she started knocking at certain rpms. A month or so later I tore it down, and one of the #2 or# 3 cylinder cam lobes was a bit worn, rotated the lifter and it was toast! Probably worse than yours, but I drove it probably 20 miles like that.

  Pulled the cam out and the front cam bearing was shot, severly pitted. Pulled the bottom end, and the crankshaft main and rod bearings had these really odd wear patterns, like the block needed to be line bored or something. Anyway, sorry for hijacking, good luck with that.
1983 Tbird with '03 Split Port V6 motor swap done! Headers, dual exhaust, 500CFM Edelbrock, 3G upgrade, Electric fan. 3.73 Gears and an FRPP Limited Slip. Five lug complete! 5-Speed conversion complete! Standalone Fuel Injection in progress...

Failed 5.0L Motor...

Reply #12
You might not see a wobble on a counter top. Put it in a drill and spin it up :hick:
2015 Mustang GT Premium - 5.0, 6-speed, Guard Green - too much awesome for one car

1988 5.0 Thunderbird :birdsmily: SOLD SEPT 11 2010: TC front clip/hood ♣ Body & paint completed Oct 2007 ♣ 3.55 TC rear end and front brakes ♣ TC interior ♣ CHE rear control arms (adjustable lowers) ♣ 2001 Bullitt springs ♣ Energy suspension poly busings ♣ Kenne Brown subframe connectors ♣ CWE engine mounts ♣ Thundercat sequential turn signals ♣ Explorer overhead console (temp/compass display) ♣ 2.25" off-road dual exhaust ♣ T-5 transmission swap completed Jan 2009 ♣

Failed 5.0L Motor...

Reply #13
Never thought about the drill trick.  That's good info to know!
84 TC 302 -5.0L/t5/7.5 locking rear and a 3.45 gear, Edelbrock Intake, Aluminum Heads, Edlebrock 65mm Throttlebody, Edlebrock Cam, 24lb injectors & MAS Air Sensor calibrated via chip,  BBK headers, Catback H pipe, Magnaflow lers :evilgrin:
:pics-stfu:

 Project Thread with pics

Failed 5.0L Motor...

Reply #14
measure to see if your heads are flat, and make sure gas dosen't leak out of the "dish" in the heads. I really wouldn't worry about them too much if those two things work out.
Quote from: jcassity
I honestly dont think you could exceed the cost of a new car buy installing new *stock* parts everywhere in your coug our tbird. Its just plain impossible. You could revamp the entire drivetrain/engine/suspenstion and still come out ahead.
Hooligans! 
1988 Crown Vic wagon. 120K California car. Wifes grocery getter. (junked)
1987 Ford Thunderbird LX. 5.0. s.o., sn-95 t-5 and an f-150 clutch. Driven daily and going strong.
1986 cougar.
lilsammywasapunkrocker@yahoo.com