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SM514 · 05-11-2015, 09:42 AM

Sorry to bring this back up but I have an update. And hopefully the next person who has this problem finds this as an easy fix.

After months of searching and getting nowhere, I had someone who claimed to be in Japan offer to help as they had a few of these jets. Long story short, PayPal is my friend and I didn't lose any money when the jets never showed up.

The problem:

I have had this block for some time now (S2 RB25). I have rebuilt it only once but she sees her share of abuse. Track events and my occasional bad example driving. So she does have a bit of work to her so it wasn't as easy to just get a new block. However that was the last chance option should all else fail.

At the last track event at Watkins Glen, I smeared my ring lands but didn't damage the block. It first came as poor starting and lower power before boost. Eventually I checked compression and found most were under 90psi and #3 and #5 were under 50. I scoped each cylinder and found all valves were intact and working well. The tops of the pistons were in good shape but I noticed the edges were a little crumbled. They were ceramic covered Wiseco pistons. (I like nitrous)

So tear down commenced.

I took the block to a machine shop I know well for a thorough cleaning and new freeze plugs. They suggested removing the jets and cleaning the oil passages as well. But to do so, they would have to drill the oil jets out. Now since I never really took a good look at them, I thought they were no more than a metered jet similar to a carb jet. I knew I could get those. They are the same as a Z32. What I didn't see was that 2 out of 3 of them have a check ball to keep the oil from draining back. The most forward one (near the water pump) is the straight through one.
https://www.dropbox.com/sc/qdhxt8isb...kbZO4R3E-64hma
https://www.dropbox.com/sc/y964p6ddr...XoUVuz12bWVlXa
https://www.dropbox.com/sc/cev47usgn...bX8DCXPJfj7wUa

I have found that the Z32 has the correct straight through jet but the ones with the check ball are larger in diameter. So I continued my search for the correct jet, but obviously to no avail.

My solution:

I decided to do some of my own machining. You will see the jet has a step in it. So measuring each width, I matched them with a drill bit. I drilled with the narrower bit first so that the wider one would MAYBE have less of a chance to be off center. I do have a drill press but not one big enough. So a hand held drill was my next option. Thankfully it worked out. Plus there is tons of meat around the holes so a mistake probably would not be terribly detrimental. Plus using electrical tape to mark the depth I needed would keep me from going too far on each bit.
https://www.dropbox.com/sc/cohz0hw45...EgjaYx4K5lLhGa
https://www.dropbox.com/sc/gig50bhsp...RYE9kTpPCz7Hfa

I do not have the part number for the forward jet, but the check ball one is 11036-1P600. My assumption would be that all RBs have these jets and would be a similar job to be replace them.
https://www.dropbox.com/sc/ylygy8pso...LBseF7E0IqQioa

Thanks for reading my rambling. I hope this saves some time for the next person. While it took me a few months to get to this point, the work itself was simple and quick.

And forgive me it this post comes out messed up or unorganized. I'm not on here a lot.

Later

05-11-2015, 09:42 AM	#10
SM514 Join Date: Jul 2013 Location: Central New Yotk Posts: 10 Trader Rating: (0)	Sorry to bring this back up but I have an update. And hopefully the next person who has this problem finds this as an easy fix. After months of searching and getting nowhere, I had someone who claimed to be in Japan offer to help as they had a few of these jets. Long story short, PayPal is my friend and I didn't lose any money when the jets never showed up. The problem: I have had this block for some time now (S2 RB25). I have rebuilt it only once but she sees her share of abuse. Track events and my occasional bad example driving. So she does have a bit of work to her so it wasn't as easy to just get a new block. However that was the last chance option should all else fail. At the last track event at Watkins Glen, I smeared my ring lands but didn't damage the block. It first came as poor starting and lower power before boost. Eventually I checked compression and found most were under 90psi and #3 and #5 were under 50. I scoped each cylinder and found all valves were intact and working well. The tops of the pistons were in good shape but I noticed the edges were a little crumbled. They were ceramic covered Wiseco pistons. (I like nitrous) So tear down commenced. I took the block to a machine shop I know well for a thorough cleaning and new freeze plugs. They suggested removing the jets and cleaning the oil passages as well. But to do so, they would have to drill the oil jets out. Now since I never really took a good look at them, I thought they were no more than a metered jet similar to a carb jet. I knew I could get those. They are the same as a Z32. What I didn't see was that 2 out of 3 of them have a check ball to keep the oil from draining back. The most forward one (near the water pump) is the straight through one. https://www.dropbox.com/sc/qdhxt8isb...kbZO4R3E-64hma https://www.dropbox.com/sc/y964p6ddr...XoUVuz12bWVlXa https://www.dropbox.com/sc/cev47usgn...bX8DCXPJfj7wUa I have found that the Z32 has the correct straight through jet but the ones with the check ball are larger in diameter. So I continued my search for the correct jet, but obviously to no avail. My solution: I decided to do some of my own machining. You will see the jet has a step in it. So measuring each width, I matched them with a drill bit. I drilled with the narrower bit first so that the wider one would MAYBE have less of a chance to be off center. I do have a drill press but not one big enough. So a hand held drill was my next option. Thankfully it worked out. Plus there is tons of meat around the holes so a mistake probably would not be terribly detrimental. Plus using electrical tape to mark the depth I needed would keep me from going too far on each bit. https://www.dropbox.com/sc/cohz0hw45...EgjaYx4K5lLhGa https://www.dropbox.com/sc/gig50bhsp...RYE9kTpPCz7Hfa I do not have the part number for the forward jet, but the check ball one is 11036-1P600. My assumption would be that all RBs have these jets and would be a similar job to be replace them. https://www.dropbox.com/sc/ylygy8pso...LBseF7E0IqQioa Thanks for reading my rambling. I hope this saves some time for the next person. While it took me a few months to get to this point, the work itself was simple and quick. And forgive me it this post comes out messed up or unorganized. I'm not on here a lot. Later