removing F-head valve cover

1952 - 1968, M38A1, M170, questions, discussions, regarding anything related to the M38a1 series.
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Bpenkala
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removing F-head valve cover

Post by Bpenkala » Mon Jul 27, 2015 9:11 pm

Hello,

I am attempting to check and adjust valves and have unbolted the valve cover from the side of the engine. I seem unable to get the cover out from the engine compartment to clean and paint before reinstalling it. Every way I try to get the cover out it is blocked by something - exhaust manifold, fuel pump, steering gear box, etc. Am I missing something obvious or do I have to remove something to extract the valve cover?

Thanks,

Brad


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Re: removing F-head valve cover

Post by Joe Gopan » Tue Jul 28, 2015 2:42 am

It will slide out with a bit of manipulation. I've done it hundreds of times. TM 9-8014 is your friend on this, Paragraph 109 a. starting on page 107 will make it a lot easier for you.
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Jeeps4Brains
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Re: removing F-head valve cover

Post by Jeeps4Brains » Tue Jul 28, 2015 4:43 am

You might need to remove the PVC assembly up to the top valve cover. I also had to remove the throttle linkage by removing cotter pins and linkage pins and the pivot bolt. I remember it being a pain to get out and those helped.

Ben might have more tricks up his sleeve though. :lol:
45' MB, ??' MBT, 47' CJ2A, 48' CJ2A,
51' M38 #1, 51' M38 #2, 51' M100,
52' M37, ??' M101A1 (1st Gulf War Vet),
53' M38A1, 53' M211, 65' M151A1, 67' M416,
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Re: removing F-head valve cover

Post by Joe Gopan » Tue Jul 28, 2015 5:22 am

No tricks, just remove layers of linkage and PCV items and slide the cover. Manual will keep you straight. replace both of the cover gaskets.
2011 MVPA PIONEER AWARD - MVPA #1064
HONOR GRAD-WHEELED VEHICLE MECHANIC SCHOOL 1960 - US ARMY ORDNANCE SCHOOL(MACHINIST) ABERDEEN PG 1962 - O-1 BIRD DOG CREWCHIEF - 300,000+TROUBLE FREE M-38A1 MILES
LIFE MEMBER AM LEGION-40/8-DAV
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Re: removing F-head valve cover

Post by Bpenkala » Tue Jul 28, 2015 6:18 pm

Ok - another concern with my valve issue. I checked the intake and exhaust valve clearances and all except one was at correct gap as per the manual (#3 intake was too close so I corrected it). I initially started this process because the engine seems to have a lot of tapping noise but I don't think one valve would cause the noise. Now I am wondering if I should go further and look for other issues since I have the valve covers off. What would be my next step? I don't want to run the engine if there is a problem that will cause more damage.

Brad

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Re: removing F-head valve cover

Post by Joe Gopan » Tue Jul 28, 2015 6:26 pm

Excess camshaft end play can cause noise. Is the Oil Line from the Crankcase to the Cylinder Head delivering oil? Is the spacer present between the fuel pump and the block?
2011 MVPA PIONEER AWARD - MVPA #1064
HONOR GRAD-WHEELED VEHICLE MECHANIC SCHOOL 1960 - US ARMY ORDNANCE SCHOOL(MACHINIST) ABERDEEN PG 1962 - O-1 BIRD DOG CREWCHIEF - 300,000+TROUBLE FREE M-38A1 MILES
LIFE MEMBER AM LEGION-40/8-DAV
7 MIL SPEC MAINTAINED MV'S
COL. BRUNO BROOKS (ARMY MOTORS) IS MY HERO

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Re: removing F-head valve cover

Post by Bpenkala » Wed Jul 29, 2015 9:08 am

I have an aftermarket fuel pump (no vacuum) and it does not use the spacer (plans to upgrade to original fuel pump when I have time to rebuild core). I turned the engine over with starter for about 30 seconds to check for oil flowing to head/rocker area - did not see any but do I need to start the engine to get enough oil pressure? It looks like oil had been moving there because it looks clean where it pools at top of head (I had recently changed oil and filter). I am unfamiliar with how to check end play in camshaft and did not see this in manual but will keep looking.

Could some of the valve collars/spacers be moving and causing noise? Is there a way to check without removing head?

Brad

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Re: removing F-head valve cover

Post by Joe Gopan » Wed Jul 29, 2015 10:27 am

You can remove the Rocker Arm Cover and observe oil circulation along the Rocker Arm Shaft, or just crack the nut at the top of the head while the engine is running to check for flow to the head.
2011 MVPA PIONEER AWARD - MVPA #1064
HONOR GRAD-WHEELED VEHICLE MECHANIC SCHOOL 1960 - US ARMY ORDNANCE SCHOOL(MACHINIST) ABERDEEN PG 1962 - O-1 BIRD DOG CREWCHIEF - 300,000+TROUBLE FREE M-38A1 MILES
LIFE MEMBER AM LEGION-40/8-DAV
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Re: removing F-head valve cover

Post by Jeeps4Brains » Thu Jul 30, 2015 4:25 am

Make sure the oil feed tube that goes from the oil gallery down near the rear of the block and up to the head is present and not clogged. That one line is what feeds the oil to the head.

Alan
45' MB, ??' MBT, 47' CJ2A, 48' CJ2A,
51' M38 #1, 51' M38 #2, 51' M100,
52' M37, ??' M101A1 (1st Gulf War Vet),
53' M38A1, 53' M211, 65' M151A1, 67' M416,
MVPA #31724

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Re: removing F-head valve cover

Post by Bpenkala » Thu Jul 30, 2015 10:01 pm

I checked and have oil delivered to head/rockers.

I have taken an audio file with my smart phone (not smart enough to tell me what is wrong) and have attached a link to it with this post (I think). If anyone wants to listen and give more suggestions that would be great. The noise I am concerned about is quite obvious - it actually is louder in the audio file than hearing the engine in person.

Here is the link - you might need to copy and past in a browser (I hope it works):
https://www.dropbox.com/s/vl1zctzy9oqpl ... 2.m4a?dl=0

Thanks,

Brad


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