09-06-2017, 07:12 AM | #1 |
Not Yet Wild
Join Date: Sep 2017
Posts: 4
|
FE350 Valve Guides
I have a 2013 XRT800 with the FE350D CW motor W/O ACR. It started making tappet like noises but I was under the impression the FE350 had HLA or hydraulic lifters & required no adjustments. Finally it started making a compression release type noise that became even more disturbing so I finally decided to investigate.
At first I thought the muffler might leaking but found everything in good order. So I pulled the rocker cover off. To my surprise I found this motor has mechanical lifters with adjusters on the rockers. OK, well maybe they just need some adjustment. Although the exhaust was a little lose at 0.007” I set it back to 0.005”. Did not fix the issue but after closer examination I finally found that the exhaust valve guide has shifted up from it’s seated position so much that when the value is depressed the top spring retainer is now hitting it. Further more, there is/was a valve stem seal mounted here that disintegrated because the guide shifted up. So I find it curious that this motor appears to have FE290 lifter setup installed from the factory, and the exhaust value guide appears to be the same as the intake value guide with the stem seal installed. According to the parts list the exhaust value stem guide is different than the intake one and has no seal installed on it. So should I put in the specified parts for the exhaust valve guide or use the intake valve guide with seal? I’m assuming the mechanical rockers are just the FE290 version and the adjustment would be the same – 0.005” for intake & exhaust. Thanks |
Today | |
Sponsored Links
__________________
This advertising will not be shown in this way to registered members. Register your free account today and become a member on Buggies Gone Wild Golf Cart Forum |
|
09-06-2017, 10:16 AM | #2 |
Getting Wild
Join Date: Sep 2016
Location: Bel Air, MD
Posts: 140
|
Re: FE350 Valve Guides
yes the 290 and 350 heads are the same set-up. Do a compression check. With what your describing, it sounds like the exhaust valve has started to actually go up in the seat. This happens quite often on these motors if the valve adjustment isn't checked.
|
09-14-2017, 09:11 PM | #3 |
Not Yet Wild
Join Date: Sep 2017
Posts: 4
|
Re: FE350 Valve Guides
I’m waiting for parts before I take the head off. Should be here around 9/26. I found this engine has variations when it comes to valve guides. Some versions have different valve guides for the exhaust & intake while other use the intake guide with oil seal for both. Maybe the latter has something to do with emissions.
Anyway, I’m hoping I just need to replace the exhaust valve guide & button it backup. I’m thinking the valve is OK. If not then I’ll have to get a new valve & check adjust the seat – ugh… With only a 150 hours on this motor I don’t know why this would have happen. Maybe the exhaust valve would be happier with the standard exhaust valve guide without the oil seal on it? According to another post CC went to the mechanical adjusters because of issues with the HLA’s? |
10-06-2017, 06:37 PM | #4 |
Not Yet Wild
Join Date: Sep 2017
Posts: 4
|
Re: FE350 Valve Guides
OK, I finally got my parts & got the head off. As can be seen the exhaust guide move about a 1/4” up from it’s home position. The oil seal on top disintegrated and the push rod was slightly bent.
IMG_0549(800).jpg I heated up the head & pushed the guide out – came right out. After getting everything cleaned-up I measured the valve stem OD’s, guide ID/OD and the head ID. My intake valve stem was 0.2736” & it’s guide was 0.2756 giving me 0.002” clearance. My exhaust valve stem was 0.2378” & it’s guide was 0.2758 giving me, again, 0.002” clearance. The limits are 0.0054” for the intake & 0.0060” for the exhaust so everything looks good here. The exhaust valve did have some carbon buildup on the guide/stem mating surface. So my old guide OD measures 0.4744” & the new ones measure 0.4752” so the new ones are 8 tenths bigger. Measuring the head ID hole for the exhaust guide yields 0.4746”. So its no wonder the **** thing moved. My measurements says the head hole is 2 tenths bigger but it can’t really slip in there, but it did push out pretty easy. The new guides are bigger by 8 tenths giving an interference fit of 6 tenths but that’s still not the recommended 0.0010” to 0.0015” for AL heads. Also, the new valve guides ID’s are not reamed out. They are undersized about 0.003” so I need to buy a 7mm reamer to bring them into spec. Don’t know why the factory does not ream them to size??? Anyway, I’m not seeing a clean solution to this problem. The valves & seats are in good condition. If I put the new guides in I’m probably going to have to regrind the seats and I’m still not going to have the recommended interference fit. So I have been thinking of using & putting the old guide back-in. I managed to straighten my push rod to a few thou (the limit is 0.020”) so I’m good there. So new gaskets, oil seals and button it back up and see how it goes. Otherwise, it’s a lot of machine work or just buy a new head assembly. |
10-14-2017, 02:54 PM | #5 |
Not Yet Wild
Join Date: Sep 2017
Posts: 4
|
Re: FE350 Valve Guides
As it turns out you cannot just replace the valve guides that easily. They are a powder metal material & require a carbide reamer to fit the valves. Also, if you replace a valve guide the valve seats will need adjustment too.
So I decide to re-use the old guides & glue them in with Loctite 640. Luckily I marked them such that I could reinstall them in the same orientation. So I heated up the head to 400F and pushed in the old guides coated with Loctite 640. I used my CNC mill so they could be quickly and accurately placed. VG-1(800).jpg VG-2(800).jpg VG-3(800).jpg After installation I gave the valves a light lapping to check their fit & everything looked good. One of the benefits of powder metal guides is that they provide their own lubricity so I decide to put new oil seals on the both intake & exhaust valve just as I found it. So I buttoned everything up using new gaskets and my cart is happy again. Time will tell if the Loctite holds … So just to recap, not all FE350 use hydraulic lifters. From the factory mine had mechanical lifters & they need to be adjusted. My head has powder metal valve guides & you just cannot replace them without doing a complete valve job. Both valves are designed to use oil seals on the valve stem with very little, if any, oil necessary between the valve stem & guide (I’m thinking this is a EPA thing). I think my problem was a latent factory defect whereas the original valve guides were manufactured with a under-size OD. The new guides are 0.0008” bigger providing a better interference fit. |
|
|
Similar Threads | ||||
Thread | Forum | |||
FE350 valve issue | Gas Club Car | |||
new valve guides bore .oo6 too small | Gas Club Car | |||
FE350 valve problem, loose rocker arm. Help | Gas Club Car | |||
What is valve adjustment Fe350 | Gas Club Car | |||
Yamaha "maintenance & Troubleshooting" Guides | Golf Carts and Parts |