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Misfires on 4,5,8. Iím going to document what I try.

 
  #61  
Old 06-12-2019, 12:31 AM
wbubble
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Originally Posted by Im50fast View Post
Bro, you are taking it to a machine shop right?
Please say yes.
Those guys are wizards and youíd be foolish to avoid them just to save a few duckets.
I admit it, Iím past my experience on this one. Iíve replaced engines before, Iíve replaced head gaskets. Iíve replaced chains and retimed a DOHC all aluminum German V8... but Iíve never removed a valve from a cylinder head. Iíve bent Ďem but Iíve never replaced them myself.

I am digging in this far so I can learn how to do it. Not so I can do it again, but so I can say I tried it once and succeeded. I asked for a welder for Fatherís Day and my wife got me a small flux core welder last weekend. I welded scrap metal for 3 hours and it was fun. I donít have anything to weld, but Iíve always wanted to try. I like to learn by researching then trying.

Worst case I wreck the whole thing and have to buy a new head and do this over. At least Iíll have learned something new (how to wreck a head!)

Iím taking my time and making reasonable efforts to take all necessary steps. Iím replacing head studs, every seal that Iíve disturbed, and checked the deck for straight with a metal straight edge and a .002 feeler. As long as Iím able to lap the new valves and confirm none of them leak, I think Iíll be good to go. My fingers are crossed, and Iím hoping for the best. If the head were out of spec Iíd have it machined.
 
  #62  
Old 06-12-2019, 04:28 AM
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I was talking about more than machining:
specifically,
1 replacing the valve seats and
2 guides and
3 measuring spring rate.

To the best of my knowledge you canít do those at home. And your engine needs it bad on cylinder four (at least).

i respect your desire to jump in and try it. I guess you and I are just very very different in regards to gambling the possibility of a do-over.
Err-bodyís different.



Im enjoying the journey with you though. I hope it all works out for you. Keep us posted and with pics too.
 
  #63  
Old 06-12-2019, 08:31 AM
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Thanks!

Before I started, the truck wasnít burning any oil at all, there wasnít any noticeable blow back via the oil filler and by hand, the guides on 4 feel nice and tight. Iíll be candid - because Iím only willing to remove one head right now, Iím less worried about bringing it to like new condition than if I were working on both sides. I want to cure the misfire.

I am only slightly worried about the valve seat, and that may be the end of my handy skills on the head. But if itís not damaged and I can lap a good seal..... we will see. Iíll take pics.

I tried removing the first valve spring last night with a $10 overhead valve compressor (itís the only option HF had) but the tool didnít match up and kept popping off. Iíll rent one today.
 
  #64  
Old 06-12-2019, 11:08 PM
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Getting the valves out was hard.


Thereís your problem.

I tried a universal overhead valve spring compressor. It didnít work.

i tried a huge c-clamp with an oxygen sensor socket on the end. That didnít work.

I found the only c-clamp style valve spring compressor in my area and I still had to use a 1/2 inch piece of pvc as a bushing to get enough squish on the springs to get the keepers out.

Im going to have a heck of a time getting them back in.
 
  #65  
Old 06-13-2019, 01:03 PM
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I still can't understand how those valves are so cruddy, and yet the intake ports show no sign of oil. I think the valve seals are o-rings - were they intact?
 
  #66  
Old 06-13-2019, 01:32 PM
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Here's my theory...

Originally Posted by Krewat View Post
I still can't understand how those valves are so cruddy, and yet the intake ports show no sign of oil. I think the valve seals are o-rings - were they intact?
Valve seals look good. They're o-ring with metal spring for structure.

Here's my theory. A few posts back I posted photos of the head gasket still on the block and some discoloration on the head between 4 and 5.

I think the valves are a symptom of a small interaction between cylinders 4-5 from a leak in the head gasket. The previous owner told me that the misfire was an ongoing problem for a long time before he parked the truck. I think he ran it and ran it and ran it with those 2 cylinders sharing compression, and cylinder 4 took the brunt of it. That caused the valves to foul, killing compression in that cylinder completely. I think the compression I read on cylinder 4 was being provided by cylinder 5.

If my theory is correct, installing new intake and exhaust valves on cylinder 4 and replacing the head gasket should solve the problem. I've already tested for cylinder blowback into the crankcase and can see no oil burning, which tells me that the rings and valve seals have been functioning properly, and the valve guides are tight. The valve seats aren't showing any damage either and through the carbon build up, I don't see any indication that the valves are damaged in any way. I'm half tempted to clean and re-use them, but I won't.

I may try my hand at lapping the new valves in tonight.

Does anyone have recommendations for an easy to use valve spring compressor?
 
  #67  
Old 06-14-2019, 05:05 AM
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Originally Posted by wbubble View Post

Does anyone have recommendations for an easy to use valve spring compressor?
I've ordered the OTC tools to set cam timing on my 5.4 but also ordered a far less expensive set that gets mostly good reviews. Since these tools will be only used once I didn't want to spend a fortune. (I'll be replacing a newly rebuilt Ford head with a warranty supplied new assembly from Ford so didn't need the spring compressor.) Anyway.........

Looking at the OTC 6684 offering on Amazon there are more than a few less costly similar tools that might fit your needs. Bottom of page:
Triton Spring Compressor Triton Spring Compressor

HTH
 
  #68  
Old 06-14-2019, 11:04 AM
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The auto parts guy told me he thought I could burn off the carbon. It didnít work. Probably not got enough.
 
  #69  
Old 06-14-2019, 11:12 AM
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You're going to need at least MAPP gas, if not oxy-acetylene to do that job

New valves aren't that much, are they?
 
  #70  
Old 06-14-2019, 11:46 AM
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Originally Posted by Krewat View Post
You're going to need at least MAPP gas, if not oxy-acetylene to do that job

New valves aren't that much, are they?
I already bought the new valves. This was just for fun and the picture looks cool.
 
  #71  
Old 06-15-2019, 03:12 PM
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New valves lapped in.

This morning I used a short section of rubber fuel line and a cordless drill to patiently lap the new valves in for cylinder 2.

Before any grinding.

Drill with fuel line on the valve stem.

After the course grind on the exhaust valve.

Intake valve after lapping.

Perfect!

New valves in place.
 
  #72  
Old 06-15-2019, 04:59 PM
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Your going to need a pretty smooth surface on head and block for mls gasket to seal.

OEM mls HG needs an RA of 20 or 30ish
A felpro mls might get away with 60 or 80 RA.

Anything more than above will leak and you will be doing this job over.

Who supplied new valves?
They look used to me.
 
  #73  
Old 06-15-2019, 05:11 PM
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I ordered a Felpro head gasket and the valves are Sealed Power from Napa.


 
  #74  
Old 06-18-2019, 11:51 PM
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Valve Springs Are Back In.

After much cajoling, the valve springs are back in and the valves are completely reinstalled. I tested all the valves in this head with soapy water and compressed air and all 10 are tightly sealed now.

All my reassembly parts arrived tonight as well. I had a 25% off Fatherís Day coupon for Oreilly online.


Ready for the cam to go back in. I need to find torque specs.

Ended up using this OHV spring compressor with zip ties to keep the spring in. It worked for 1/2 the keepers and for the others I used the same tool with my body weight. Phew!
 
  #75  
Old 06-19-2019, 09:42 AM
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Note to self, if I ever need head work, just replace entire assembly.
 

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