Problem with osco riser gasket??

[crazy charlie]

I put new man and risers on 1 of my mercruiser v8,Osco brand.There is a 1" rust line around the bottom of the riser and 1/2" onto the mating surface of the manifold after a short season of use.It is tighented properly.Do I have a faulty gasket???? Charlie

 

[rodbolt]

Re: Problem with osco riser gasket??

hello <br /> charlie<br /> what type of gasket material was it? some of the new stuff is teflon coated and cannot be used with any sealer. did you use any type sealer? I use perfect seal on the paper gaskets. but a small rust line appearing is normal. especially in salt or freshwith a high mineral content. if its not weeping water and the gasket is torqued and checked periodically I dont see a problem.<br /> good luck and keep posting

 

[Ryoken]

Re: Problem with osco riser gasket??

all of what Rodbolt mentioned... and Perfect Seal is great stuff..<br /><br />one other point to mention. once exhaust jobs are assembled i always douche all joint areas with appropriate paint... if gasket surfaces are bare to edges, rust will tend to creep away from the joint even with no leaks . hitting the area with paint after assembly helps stop that...<br /><br />i have to deal with my customers for years later, so those little things help keep them happy...

 

[crazy charlie]

Re: Problem with osco riser gasket??

Hey Redbolt.The gaskets were gray/black and seemed to be a regular crushed cardboard-paper type gasket.It came with the riser and manifold and bolts.I was considering taking the riser off and getting a new gasket and spraying it with permatex Hi-Tack before reinstalling it.The risers on the other motor are old and have no rust on them at all.I assume there is a slight seepage .Charlie PS the rust line drives me NUTS!!!! a few times a year,I clean off any tiny rust spots that may appear on my motors and paint the spot.

 

[rodbolt]

Re: Problem with osco riser gasket??

hello<br /> merc has a shiney gray gasket out that feels like teflon. use it on clean metal with no sealer. seems to work well. paint everything when your done. Hy-tack seems to work well on the paper gasket types <br />good luck and keep posting

 

[Ryoken]

Re: Problem with osco riser gasket??

if you put it together dry with paper gaskets it will generally leak at some point. mercs go together dry, all others should get coated on all surfaces with Perfect Seal. much better than hytack for exhaust. and again, paint when assembled..

 

[yoced]

Re: Problem with osco riser gasket??

Charlie, can you tell me more about the gasket and which type of manifolds/risers you bought? I would also like to know from whom you purchased the parts if that is ok. I am trying to track down gasket styles and problems, especially with the Osco black gaskets.

 

[crazy charlie]

Re: Problem with osco riser gasket??

Yoced,I ordered the risers from Basic Power and I think the gaskets were a dark gray,pretty thick,they came in the same box so I assume they are from Osco.Charlie

 

[navigator336]

Re: Problem with osco riser gasket??

I have been told that for the paper based gaskets that you should use a generous amount of Permatex #2 as it will not harden. I was also told to replace them every two years if in salt water. The last time I replaced gaskets, I switched to the composite impregnated ones. The factory said they are impregnated with silicone and to use 3M Hi Tack 77 on the gasket and the metal surfaces. I did, and as far as one can tell without pulling the risers, all is well after one year.

 

[dmorley]

Re: Problem with osco riser gasket??

I'm not sure what you have for gaskets. My Osco gaskets came in a separate Osco box and are a green/tourcoise (sp). The Osco tag reads: "The installer should remove all paint from the gasket surfaces before assembly. Use acetone or lacquer thinner to remove the paint. Do not scrape, sand, file or use high speed rotary gasket removers. Gaskets should be installed dry. Do NOT use gasket sealers, silicones, or compounds." The Osco gaskets were small change so if you have any doubts order them and head off bigger problems. Also, as indicated before Osco advises painting to prevent rust. They also say to only use grade 5 bolts (and include them with their gasket) as stainless and grade 2 will not hold their torque and can cause problems. I don't think you have Osco as they are very clear about the do's and don'ts.

 

[yoced]

Re: Problem with osco riser gasket??

Charlie, the gaskets coming in the box from Basic don't mean that they are Osco gaskets. Basic tends to mix and match components on whim. However, <br /><br />Osco did make a black paper/rubber composite gasket for a while. Those gaskets were usually inked in white with the Osco part number. They had enough problems with the manufacturer of the paper to switch to the turquoise gasket material later.<br /><br />What I would suggest is that you call Osco directly (1-800-762-6726)and talk to their technical services manager, Kerry Stark. He is quite good at diagnosing leak problems, and of course has something at stake here since you have bought his parts...

 

[crazy charlie]

Re: Problem with osco riser gasket??

Thanks Yoced and Don.Don you struck a memory with the green gasket!!!!!!! I must have been thinking about another gasket I once used but yes they are green.I called Osco and the advise they gave me was to order new gaskets.They stated that they dont recommend sealants simply because most people use too much and the wrong kind of sealants.He told me it was good to use sealants as long as you dont overdo it.I mentioned Hi Tack because it is hard to overdo it with an aerosol and he said that would be fine.He was evasive when asking what to use and he only answered the specific question that I asked without any explanation or advice.It sure seemed I was doing most of the talking.This problem I am having may be a reoccuring problem that they are having with the gaskets.I have never spoken to a techline and had to pry for a solution.I will take them apart and start from scratch.Charlie