re-installing drain plugs

[rebars1]

When re-installing the threaded drain plugs on the manifolds and cylinder block is it recommended to use Perfect Seal on the threads, or will they seal like tapered pipe threads? (Merc 888, Ford 302).

 

[Bondo]

Re: re-installing drain plugs

I'd Seal them.....

 

[Laddies]

Re: re-installing drain plugs

Use care and don't over thinghten them and you won't hate yourself in the fall---Bob

 

[yoced]

Re: re-installing drain plugs

They ARE tapered pipe threads. But any thread can leak. <br /><br />Like Bondo says.....

 

[jonmurr]

Re: re-installing drain plugs

A little teflon sauce on the lower threads goes a long way towards removal in the fall. Also be careful of the torque on pipe plugs. If the two sets of threads are in reasonable shape, a little turn past snug should make them seal. Rust, old sealer, silly-snot, etc. makes people run them in till they pop out the other side. <br />Jon

 

[JasonB]

Re: re-installing drain plugs

Agree with the above, A little teflon...<br /><br />Another thought: Any advese effects to replacing the plugs with petcocks? I did some experementing with my 888 and 1/4" NPT radiator drans are a great fit on my aftermarket manifolds. Pulling 8 plugs just from the maifolds temselves on my boat is a half day job due to trying to get a tool into a small working area. The drains would be much easier.

 

[Don S]

Re: re-installing drain plugs

If you have a thread compound with teflon in it, that's fine, but forget "teflon tape" that stuff causes more leaks than it cures. Mostly because people don't know how to use the sh#2. I see wrap after wrap on leaky fittings, over the end of the fitting, wrong way, just no telling what will happen, then if you have too much TT and overtighten the fitting or plug you can actually crack castings.

 

[jonmurr]

Re: re-installing drain plugs

My OMC has great heavy brass petcocks in the block and manifolds. They may be this things only redeeming value. THE OMC # is 379757. May still be available from Bombardier. Auto ones would work, I think, would just have to watch the center part for rapid corosion as it is usually plated steel.<br />Jon

 

[lakelivin]

Re: re-installing drain plugs

JasonB,<br /><br />I have petcocks but pull them so that I can ream out the drain holes with a piece of wire when I drain. Learned I needed to do this the hard way 7 or 8 years back when scale or whatever blocked complete drainage of one of my exhaust manifolds and it cracked from freezing.<br /><br />But I still like the petcocks, easy to spot and take off with just a pair of pliers... <br /><br />My boat is an '89, don't know how old a boat needs to be before this might be an issue, but even if I get a new(er) boat, I'll still keep a piece of wire handy and not take any chances...

 

[nms1991]

Re: re-installing drain plugs

Lakelivin I see more boats with cracked engines or manifolds because people assume that ther boat is drained when they pull plugs or petcocks and no water comes out, aslo a ziptie also works well. Automotive style have sheetmetal tee type handles that seem to strip out. I prefer the mercruiser version that is all brass.

 

[rebars1]

Re: re-installing drain plugs

So...is Perfect Seal OK to use or should I use something else? <br />I don't need to winterize, so I don't need to drain the system as much as others. I don't know if the guy before me drained it since he installed a rebuilt engine (I'm guessing about two years ago). However, I was surprised at how much junk/rust came out.

 

[JasonB]

Re: re-installing drain plugs

I believe my repair manual advocates the use of perfect seal as a anti-seize, I think it would work for what you want it for. I used a permatex product that is similar with good results.

 

[Lou C]

Re: re-installing drain plugs

The seal fine when you tighten them, just a little more than hand tight. If you are worried about corrosion you can smear the threads with OMC triple guard grease, I use that on fasteners that will be exposed to salt water and it works well.

 

[rodbolt]

Re: re-installing drain plugs

hello<br /> yep I am with DonS<br /> throw the teflon tape in the trash. I love/hate the stuff. I wont use it unless the srevice manual calls for it specifically.<br /> I love it cause I have made a lot of money due to the problems it has caused. I hate it for the same reasons.<br /> if you drain it a lot go with the brass petcocks and realize that sometimes you have to clear them.<br />perfect seal will work fine. bombardiar has the same stuff, called gasket maker I think, in a small can.