1. Registration trouble? Please use the "Contact Us" link at the bottom right corner of the page and your issue will be resolved.
    Dismiss Notice

F134 Exhaust Tappet Sticking

Discussion in 'Early CJ5 and CJ6 Tech' started by Scott Sherraden, Sep 30, 2020.

  1. Oct 3, 2020
    Keys5a

    Keys5a Sponsor

    Florida Keys
    Joined:
    Jan 23, 2014
    Messages:
    2,978
    I would stay away from that Bousfield seat cutter unless your into collecting obsolite tools. Check out Neway cutters. Much better system, but can be very expensive. At least you can buy individual mandrels and cutters, and the cutters can be used on a wide range of seat diameters. Yes, you'll need at least 2 or 3 (or more) cutters; 30 degree, 45 degree, and 60 degree for example. If simple valve lapping doesn't fix the issues, its often best to leave this type work to the machine shop for their knowledge and equipment.
    -Donny
     
  2. Oct 3, 2020
    Keys5a

    Keys5a Sponsor

    Florida Keys
    Joined:
    Jan 23, 2014
    Messages:
    2,978
    A problem you may encounter when replacing guides is a new guide often doesn't insert exactly at the same angle as the original. You always needed to rework the valve seat based on the fresh guide position. When I replace guides, only about 1 in 8 actually have the valve concentric in the seat where lapping would clean up the seat.
    If you are going to try this on your own, I remove "blind" guides by tapping threads in the bore and using a deep socket (or correct tool) and a grade 8 bolt to extract the guide. A guide installation tool has a pilot with a shoulder, and is usually made it insert in an air hammer. I have cracked guides attempting to install them with a press. Guides need to be reamed to size after installation for proper clearances.
    -Donny
     
  3. Oct 3, 2020
    Scott Sherraden

    Scott Sherraden Member

    Kansas
    Joined:
    Jul 7, 2020
    Messages:
    59
    Here is the method I'm going to use...
     
  4. Oct 3, 2020
    Scott Sherraden

    Scott Sherraden Member

    Kansas
    Joined:
    Jul 7, 2020
    Messages:
    59
    Good advice. So, I'll install the new guides first, and then I'll rework the seats using one of the tools suggested. I'll research the Neway cutters, that seems like the way to g.
     
  5. Oct 3, 2020
    Scott Sherraden

    Scott Sherraden Member

    Kansas
    Joined:
    Jul 7, 2020
    Messages:
    59
    I'm not sure but it looks to me that someone possibly already installed hardened seats before. I've only had the car a short while. I can tell that there is some sort of insert - not sure if they were that way from the factory or not.
     
  6. Oct 3, 2020
    Keys5a

    Keys5a Sponsor

    Florida Keys
    Joined:
    Jan 23, 2014
    Messages:
    2,978
    If you see an insert, usually shiney stainless look, that is a replacement hardened seat.
    -Donny
     
  7. Oct 3, 2020
    Scott Sherraden

    Scott Sherraden Member

    Kansas
    Joined:
    Jul 7, 2020
    Messages:
    59
    Do you have the Neway cutters? They are very expensive but I think I'm going to go that route. Looks like I need the 30, 60 and 46 degree (FSM says it is 46 degree spec). Wondering what pilot size I need. Send me info on what tools you used, if you have them! I want to make sure I buy the right stuff.
     
  8. Oct 3, 2020
    Howard Eisenhauer

    Howard Eisenhauer Super Moderator Staff Member

    Tantallon, Nova...
    Joined:
    Nov 22, 2003
    Messages:
    6,605
    Find an old-timey engine rebuilder- back in the day they would do flat head exhaust seats with the engine still in the vehicle using a dingus that bolted to the block using the head bolt holes. Will be much easier to tow your jeep there than pulling the engine.
     
  9. Oct 3, 2020
    47v6

    47v6 junk wrecker! 2020 Sponsor

    Washington DC.
    Joined:
    Oct 25, 2006
    Messages:
    4,976
    The only way to do this right is to take the block to a machine shop to cut in new guides and then cut out and install the seat, then machine the valve to fit. They aren't always in the same exact place when you replace them. You're also going to need 4 new exhaust valves.

    You can try and do this on your own, but without any previous experience, your results may not be amazing.

    If you're going this far into the rebuild, you should just go all the way and fix all the worn and broken parts... or just fix the bad #3 valve and guide with knurling and a good lap job. Thats a just about as close to free as you're going to get.

    There are no clever tricks or magical thinking that can make mechanical parts work together properly for long periods of time. The right set up, tools and knowledge of the correct tolerances are all required and you pay for them and the skill of the machinist with years of experience to give provide you with good work. This is not cheap and it shouldn't be. Quality seldom is. Finding a qualified interested machinist wiling to take this on is another issue unto itself.

    Another option is to find a good running F4 134 or another power plant transplant of your choice.
     
    dozerjim likes this.
  10. Oct 3, 2020
    Scott Sherraden

    Scott Sherraden Member

    Kansas
    Joined:
    Jul 7, 2020
    Messages:
    59
    I've been reading quite a bit on the Neway valve cutters and I am going to give it a try on my own. This is a well made system. They design these tools for this purpose exactly, for shop use by non-machinists Going slowly and carefully I hope to have good results. I plan to be very conservative on cylinders 1,2 and 4 which aren't too bad. I'll have to remove more material on #3 but I think it is well within the range that new valves will give me.

    Yes I am going to replace all 4 valves.

    What have I got to lose? If I totally butcher this up, I can always have a machine shop ream it out and put in new inserts.

    I'll let you know how it goes!
     
  11. Oct 3, 2020
    Glenn

    Glenn Kinda grumpy old man Staff Member

    Apopka, Fl
    Joined:
    Sep 21, 2002
    Messages:
    10,538
    Make sure your camshaft didn't get any damage from the stuck valve issue.
     
  12. Oct 3, 2020
    Scott Sherraden

    Scott Sherraden Member

    Kansas
    Joined:
    Jul 7, 2020
    Messages:
    59
    Good idea, I am planning to drop the oil pan anyway, so I'll be able to inspect the cam lobe.
     
    Glenn likes this.
  13. Oct 4, 2020
    Keys5a

    Keys5a Sponsor

    Florida Keys
    Joined:
    Jan 23, 2014
    Messages:
    2,978
    As you have probably found, there are many different Neway cutters available. Most of mine are double-sided, that is they have two different cutting angles on each cutter. The other differences are diameters. I have cutters that range from extra-small (my term for lawnmower size valves) to large for 2 1/2+". Keep in mind F-head intakes are large, around 2" diameter. If I recall, the Jeep valve stems are 11/32", same as sbc and sbf engines. I have used Chevy 2.02 intake valves on F-Heads. Double check the stem diameter before buying the pilot mandrel.
    Some of my cutters are listed below, organized by Neway #, cutter angle and then by general size. You may be able to get a cutter that can be adjusted to cover both intake and exhaust seat diameter with the same cutter.
    #621, 15 x 46, small
    #626, 15 x 60, small
    #642, 31 x46, medium
    #643, 15 x 60, large*
    #651, 15 x 46, large
    #652, 31 x 46, large*
    The two cutters with the * might be a good pair that can cover both the F-134 valve seat sizes. You'll need a mandrel to fit the guides, as well as a T-handle to manually turn the cutter. The mandrels can be adjustable, or tapered. You might need a tapered 11/32, or 11/32 +.002 size, provided that is the correct stem diameter on an F-134. Tapered pilots are noticably cheaper than adjustables.
    You'll also need accurate digital caliper to measure stems, faces, and margins, as well as actual seats you cut.
    This all will be an investment, and you still might need seats replaced if they are too recessed or otherwise damaged.
    Hope this helps!
    -Donny
     
    Fireball likes this.
  14. Oct 4, 2020
    Scott Sherraden

    Scott Sherraden Member

    Kansas
    Joined:
    Jul 7, 2020
    Messages:
    59
    Thanks Donny good info! I found some good deals on Ebay today, I picked up a used #622 cutter (31 and 46 degree) which is the perfect size for the 1.5 inch diameter exhaust valves. Scored that for $100, which is half the price of new. It's a 5 cutter tool not the 3 cutter. I also picked up a used #270 which is the 1-1/8 60 degree cutter. I scored that one for $50. It covers up to the 1.5" diameter needed.

    So, now I just need to find the correct pilot and a T handle. I will wait until my new valve guides come in, so I can check the exact inner diameter.

    The exhaust valves on the F134 are just under 3/8 (.372 give or take). My old valves measure about .369-.370 dia.

    I only plan to do the exhaust valves. My intake valves lapped up very nicely, they don't see the wear that the exhaust valves do of course.

    I will be anxiously awaiting all of the valve parts, and tools, so I can get started! I know that 3 of my exhaust valves are in good shape and they will be just fine. Time will tell with the one bad seat, but I'm really hoping I can get it cut and still have the lapped portion in an acceptable spot on the new valve.
     
  15. Oct 4, 2020
    Scott Sherraden

    Scott Sherraden Member

    Kansas
    Joined:
    Jul 7, 2020
    Messages:
    59
    I dropped the oil pan earlier today and had a good look at the cam. All good, the lobe is fine (still looks new, this cam only has about 50 miles on it).
     
    Glenn likes this.
  16. Oct 9, 2020
    Scott Sherraden

    Scott Sherraden Member

    Kansas
    Joined:
    Jul 7, 2020
    Messages:
    59
  17. Oct 9, 2020
    Scott Sherraden

    Scott Sherraden Member

    Kansas
    Joined:
    Jul 7, 2020
    Messages:
    59
    Look what came in the mail this week!!! I have my work cut out for me this weekend.

    New exhaust valves, springs, and keepers.

    Vintage KD tools 3/8 valve guide driver and vintange Blue Point tools flathead valve spring compressor!!! I love vintage tools so glad to have these!

    Used Neway valve seat cutting tools, Neway wrench and pilot.

    Can't wait to fix up my exhaust valve train this weekend, and then get the engine all put back together. I am really hoping for great results in refreshing the entire exhaust valve train. I'll let you all know how it goes!
     

    Attached Files:

    Fireball likes this.
  18. Oct 9, 2020
    Scott Sherraden

    Scott Sherraden Member

    Kansas
    Joined:
    Jul 7, 2020
    Messages:
    59
  19. Oct 9, 2020
    Scott Sherraden

    Scott Sherraden Member

    Kansas
    Joined:
    Jul 7, 2020
    Messages:
    59
    This is what the exhaust seats look like on cylinder 1, 2 and 4. Not bad at all really. I was getting good compression on these 3 cylinders. I plan to touch them up with the Neway valve seat cutters, but very conservatively.
     
  20. Oct 9, 2020
    Scott Sherraden

    Scott Sherraden Member

    Kansas
    Joined:
    Jul 7, 2020
    Messages:
    59

Share This Page

New Posts