Converting EMI Thunder wet passage riser gasket joint to dry.
 

I ordered fittings, hoses, gaskets, and modified filter bracket to keep the water away from the gasket joint. My 502 HO Gen VI gulped water and will fix it after Christmas. Eddie Marine says to fill the passages about 1/2" deep with marine grade silicone to keep the water away from the gasket...wouldn't welding the passages shut be better?

http://i690.photobucket.com/albums/v...7/IMG_2189.jpg

How do you know the water came from the joint and not from reversion????
I don't see any trickle lines from the water passages

They could be welded but need to be careful of the heat, it can cause distortion. Not a fan of silicone, it will not last and will come loose, guess it will go right out the exhaust later.

Also agree don't see signs of water leak at the surface. What does the elbow surface look like?

Griff-Not sure...want to cover as much as possible. Can you tell me what that speckling is? The bulk of it is around the #5 exhaust port which had the worst signs of water. From the gasket joint there is 80% of that between the gasket & the heads vs. about 20% between the gasket joint into the riser. Also has signs of steam cleaning #5 in the manifold. Ether way, it's getting a tear down due to (minimum) #5 rocker ball fragments, twisted intake push rod, & gold in the oil filter. I'd like to reduce the future possibility of water involvement between the cam & exhaust riser design...to get the motor back to more reliable EMI recommended no more cam duration than 225/225 @.050 duration with the stock style aluminum risers (which is the plan)...They also said they haven't used that gasket joint design in over 10 years due to water leaking in (that's easy enough to do)... I'll do what the builder suggests but THIS boat isn't worth an additional $3k for all new exhaust just to fit the existing cam. I plan to use the existing Corsa Captain's Choice exhaust (with the new harness & solenoids). Thanks for the help. Would you trust Marine Grade Silicone to keep water away from the riser gaskets?

Already started some cleanup http://i690.photobucket.com/albums/v...7/IMG_2202.jpg

I had mine welded up on a boat I had years ago. Ran it a few years before I sold it without issues.

Try to keep the weld just below the surface to minimize having to true the surface back.

I welded up mine. I had leakage before. I have not had any issues since welding mine up. I have stainless risers though, so the passages were useless anyways.

I don't weld...what do you think it'd cost to fill all16 passages @ a welding shop?

85-90 per hour, prep,clean and weld 2 hours

With the aluminum that dirty, do they only need to clean up the inside edges of the passage? Also thought about Marine Tex Epoxy or JB Weld High Heat...

I would make aluminum plugs and weld them in

That sounds good...how thick/deep would these plugs ideally be? Friction fitted then welded?

1/4-3/8 thick enough to tap them in. tight enough so they don't fall out when you start to weld

thank you

No epoxy will hold.

Welding is the way to go, and the closer the weld or other is to the top surface, the more likely you will need some resurfacing.

Tell me if this would work, 5/16" aluminum all-thread or rod, create a "shelf" with a step bit and recess the rod for the welder...trueing up the surface is no problem if needed. The passages are about .3" wide by 1.5" & 2" long with .5" depth to play with.

I would make a piece of flat 1/4 to 3/8" aluminum cut to fit in the opening. Clean all of the surfaces that are going to be welded so you dont have to oay for them to seobd a bunch of time on that. Then tap the center of all plugs so they can be held up with a small bolt. Send it to a good welder and let them weld the plugs in. They can then take the bolt out and weld that hole shut. If you do all of that little prep work it won't cost as much for the welder. He will just have to weld them in. You get them back and true up the surface and your good.

Dropped em off at the welder yesterday...my spare time lately is worth the $95 per hour:drink::drink: & he's gonna do it all, including resurface.

That is the way to do it

Finally got these manifolds ready...but tell me if this a problem...I took all 4 pieces to the welder to fill the passages (the studs were still in the manifolds). When I took them to another machinist to clean up the surfaces they said the aluminum threads stripped out & needed timeserts, then a resurface...They look real good, but I've never used thread inserts before.

So tell me if this is a problem or not...I don't know if the original studs actually reached into the water jackets of the manifold (I did not pull them). Tonight I threaded the new stainless studs into the timeserts & they pretty much insert to varying depths...some penetrating too deep to get a washer & nut on. Are the studs SUPPOSED to loosely screw in at the proper (equal) depth and then rely totally on a thread sealer (ARP?) to keep the water out of the very same joint I just welded up? What's the proper method for studs, timeserts, and thread sealer?

http://i690.photobucket.com/albums/v...7/IMG_2278.jpg

http://i690.photobucket.com/albums/v...7/IMG_2279.jpg

Just put them in to the correct depth, I would use Yamabond #4 on the threads, hold the stud with the allen while tightening the nut. all will be good

Thanks...Would you use it on both sides of the gasket, too or RTV like Ultra Copper?

I also have the EMI exhaust and the studs do not make it into the water jacket. I did have one go in a bit further then the others but could still get the washer and nut on. If your studs are loose just sitting in the threads then I'm thinking they may have been installed using cheap tools. Cheap taps can throw tolerances off.

The studs are loose fitting in the insert until they reach the bottom. The inserts are not loose in the manifolds. I suppose I can get some longer studs on the few and use a good sealer...but it seams like the thread contact would be the seal-point, not the bottom. Were your EMI manifolds the newer dry flange or the older style wet flange joint?

They are the newer dry joint, about 4 or 5 years old now. Suffer from CRS so everything starts blurring together:confused:

Doesn't the stud have to thread to the bottom of a time-sert which creates the anchor into the base material (manifold)...if so I would need some longer studs.

class6-would you do the stud set up allowing to cure before attempting to clamp/torque to 30#? Or try to make it happen all at once?

All at once so everything sets in place. When you tighten the nut while holding the stud. nut and insert become tight.

Thanks for the response...would you also use that stuff as a gasket dressing, light smear?

I use old school Indian head. I still have cans that are 25 years old. Still works great. What gaskets are you using

Referring to the emi riser gasket at that joint between riser and manifolds.

Yes

If they use a graphite compound type. I wouldn't put anything on it

I think emi recommended hi temp sealant.

I installed mine dry and have no issues. I removed one of the manifolds this season to replace the starter and the gasket showed no signs of leaking