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Big mistake - need help

Matthew Dombrowski

Jet Boat Lover
Messages
18
Reaction score
0
Points
80
Boat Make
Yamaha
Year
2007
Boat Model
SX
Boat Length
23
Hey what's up guys in new to the forum, I'm
New to owning a Yamaha jet boat, and I'm
New to tearing down my engines to the cylinder jugs. I snapped a spark plug in each of my motors, couldn't get them out (easy outs, wd40) so I had to remove my heads. Had no idea what exactly it was that I needed to mark while taking these off. I have the service manual but here is My problem. Removed the head and the exhaust and intake valve (pads) fell out when my buddy turned it sideways. They all have numbers on them I.e. 190, 191,196 etc. how in the hell do I put this mess back together and get this engine back to where it needs to be ? Currently my heads are in a valve machine shop to do them and they said -- whoaaa where are the lash caps and the pads ?! I'm like they are home why ? He's like those need to be back in the same hole they came out !! What the hell do I do now ? I'll gladly give them to the valve shop but my manual says to make note of where they came out for reinstalling but I obviously didn't do that! The Timing is being reset and a new chain too ! So I'm not worried about that aspect. These valves need to be right for sure!!
 
Oh man, i don't know much in that regards but wouldn't new valves need to be seated fresh so would that be an alternative?
 
That's a true statement, so maybe I should just order all new (pads) and lash caps ? Idk exactly what route to take. It's at the head shop now getting cut and the valves inspected/ spark plug getting drilled out.
 
I think I'll wait a few days before taking that leap- I'm also going to attempt to call my dealer and ask
Them what my best bet is. I'm
Sure I'm not the only one to ever make this mistake and the real question is what's the remedy to bail
Out of this. I have all the lash caps and all the pads and they all have numbers on them.
 
Well, you have a lot of note taking and work ahead. This is my understanding of how to do it.

1. Put the head back onto the block with new head gasket (going to need a torque wrench & degree/angle torque gauge)
2. Then place a shim under each cap as a starting point. Mark down on paper exactly which # shim went with each valve)
3. Reassemble the cams/timing chain making sure to set correct timing
4. Check valve clearances (for all 20 valves) and make note of all 20
5. Find the factory values of each shim # and add or subtract the additional clearance needed to get within spec. Then figure which # shim matches the final value.
6. Next, dissasemble the cams/timing chain
7. Remove and swap shims that are out of spec
8. Reassemble the cams/timing chain making sure to set correct timing
9. Recheck valve clearances and repeat until all are within spec.

If all the shims for both heads were removed at the same time, I'd probably start with one engine and put as many shims in that had a "mid range" value in. I would think that it would be easier to readjust slightly up or down from there. Then try to use the remaining shims on the second engine. Depending on what type of work was done on the head, it's likely you'll need to buy a few additional shims to get everything back in spec.

Disclaimer: I'm not a professional, haven't stayed at a holiday inn, I'm posting this from memory, haven't ever done this specific task, but have researched this since I had to do a complete tear down of one of my engines and combed over my service manual. So results may vary ;)

Here's a lengthy video that might help.

 
With a feeler gauge, knowledge of factory valve clearance values and the process of elimination it can be done. If the cams were left in, not all should have fallen out. And as you know by now those #'s represent a specific shim thickness used on these solid lifters to adjust valve clearance from the cam lobes.
 
Brings me to a question that has probably only been mentioned in passing before : when do these engines really need a valve job? Heard rumors it was at like 300 hours or something once. I am probably at that now.
 
Brings me to a question that has probably only been mentioned in passing before : when do these engines really need a valve job? Heard rumors it was at like 300 hours or something once. I am probably at that now.

I think the manual says to check clearance at 200 hrs. Not sure the difference between a valve job vs. check/adjust clearance, but in in my mind valve job is pulling head and resurfacing. That can't be required every 200 hrs. I'm not a mechanic but have been a helper on several older chevy small block rebuilds.
 
Ok, all good stuff! Thanks guys - now problem is this- I need to get a feeler gauge and I also need to find out the factory values of the "pads" I'm
Thinking of it this way- they are exact engines so If I figure out 1 engine I may be able to write that down as in the values and blue print it over to the other engine. I'll
Cross my fingers and check the values and clearance with a feeler Gauge. Where would I be able to reference the factory values from yamaha?
 
I think the manual says to check clearance at 200 hrs. Not sure the difference between a valve job vs. check/adjust clearance, but in in my mind valve job is pulling head and resurfacing. That can't be required every 200 hrs. I'm not a mechanic but have been a helper on several older chevy small block rebuilds.
I would see a valve job necessary only after a compression/leak down test shows a loss of compression over a short amount of time and ya, that would mean pulling a head. But checking valve clearance between the cam lobes and shim with a feeler gauge is much less work when you can turn the engine over by hand slowly. Now that being said, I have not checked my 20v Yamaha engines yet, with less than 150hrs, but I have done this a few times after putting in a higher profile cam and bigger valves, into solid lifter interference engine, to reset the valve clearances on my 8v, 1.9lit. 83 GTI rocket.
 
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What shop are you using, and how much did they charge? I'm going to need head work on mine. You're gonna need new shims if they grind new seats. There is a big chart in the manual. Just guess, record the shim values for each valve, measure, then buy the correct shims.
 
If your machine shop can't do that, you may've picked the wrong shop. It is an easy operation though, and you can do it with the head off the block. You definitely don't wanna try to do one head and copy onto the other - they will all be different, especially if they do a valve grind. But boy, if they do a valve grind and don't know how to setup a solid lifter, that could open up a whole new can of worms. I had a head done a couple months ago where they ground too much and there wasn't a shim in the world small enough. They had to redo it and put new seats in.
 
I have not done this on these Yamaha engines but I have done the procedure on cars and motorcycles. The idea is keep the lash within tolerance per the manual. If they all dropped out you can still measure the gap without the shim to figure out what shim goes there. Keep in mind that these may have needed adjustment already so there may not be a match just close. Once the heads are reworked you will need new shims anyway to adjust them to spec. I looked at my service manual and after you have checked the gap you have to remove the cam shaft to replace the shim so keeping the right shim with the right value is critical due to the previous measurement that should have occurred. In your case measure the gap and then find the appropriate shims to fill the gap per spec. As mentioned above you will probably need some new shims anyway. Again, I have not done this on my boat or an engine like yours but the process is the same adjust the gap to spec either with a shim or a tappet adjustment.
 
Where can I buy like a general pack of shims ? (Pads) also I spoke to the Yamaha dealer about it and they said they may entertain doing the job for me--- which I don't have a problem paying considering they have the "general shim kit" -- they can do the valves and set my Timing for me. I know
For fact I can put everything else together and torque it. I'll call the head shop and make sure they don't cut the head I just want it cleaned up underneath. Because then that from what I understand can change he Depth for the valves within my cylinders. I have a shop manual with the same pages the nice gentleman posted up. I'm mechanically inclined but I just don't have the proper experience yet. I'm humble enough to admit that and the best thing I did was to take it apart so that way I can understand how this boat works inside and out. What does a valve adjustment run ? Typically
 
I have a shop manual with the same pages the nice gentleman posted up.
"You talkin to me?" LOL. Its been a while since i've been referred to as a "nice gentleman.":rolleyes: I will make sure to show my wife your post. Maybe she will stop calling me "dumb ass". As far as your other questions, the dealer should give you a quote/estimate on the valve adjustment. Be ready for sticker shock. Shim kits can be found on-line for $80. How many hours on your engines?, and if the oil was changed regularly, your existing shims may not show out of spec. wear. I might try setting the lash using the existing shims with a micrometer to measure shim thickness, write the thickness on each shim, and a feeler gauge for clearance (lash). If you end up out of spec. order new shims. There are a lot of people here with many hundreds of hours on there mr-1s and have not checked valve lash and they run fine. And I am sure you know by now to put anti-seize on your new plug threads. Good luck.
 
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Thanks for all the help guys, I'm waiting on the heads now. Spoke to a few race engine mechanics for cars ??? I'm sure they can figure it out from experience and common knowledge. I think my best bet is to have Yamaha dealer do a valve adjustment, set my timing, and put me on my way. I can do my head gaskets, bolt down the heads - bolt up exhaust, then send it to them with the lash caps and pads to check clearances as they set the timing. I bet it'll be 300 to 500 an engine. I'm hoping it's less than that honestly - but looks like I'll kill 2 birds with 1 stone? I'm going to bring these lash caps and pads to the valve shop tomorrow with the manual - is it possible they can check it without the cam shafts or do I bring them with me so they can check the clearance ? Can you check the clearance without setting the timing? As in can you do it off the block with just the cam shafts and the appropriate hardware? Hrs I'm not sure on.
 
Yes, they will need the cams and they can do it with the heads off.
 
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