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Lance
09-28-2004, 12:09 PM
I like the thread going on about anti-freeze and thought I would add a question about how often people remove the drain plugs on the back of the exhaust manifolds. I tried to get them out a couple of times but didn't have the right tool. Finally I made a concerted effort to get them out in about 2000 for my 1987 Prostar 190 and they were both loaded with rust particles. I flushed for about 5 minutes before it finally became completely clear (or very close at least). I did it again a couple of years later and more had formed but not nearly as much. I would say the first time I got a full cup of particles.

Anyone have similar experience and / or recommendations on how often this should be performed? I assume eventually this could impact the flow rate of coolant (water) although I never had any temperature problems.

Lance

jimmer2880
09-28-2004, 12:43 PM
I do mine during my winterization process. When they're out - I also stick a hose in the front & use a wire coat-hanger at the rear to get out all flakes, etc.

jimmer2880
09-28-2004, 12:43 PM
Ohh yea - the "special tool" on my 95 is just a 1/2" drive ratchet (no socket)

Lance
09-28-2004, 01:23 PM
Jimmer2880, that is my special tool now that I have the replacement plug with a square socket. The previous plugs had a hex socket and I took a long hex nut and put one end in the plug and the other end in the socket and it twisted the nut appart. I ended up getting a hardened piece of hex stock that did the trick. Since then I haven't had a problem now that I wrap in teflon tape and have the square type drive type.

Lance

bfinley
09-28-2004, 02:05 PM
I use a 1/2" rachet too!!

jimmer2880
09-29-2004, 07:32 AM
Jimmer2880, that is my special tool now that I have the replacement plug with a square socket. The previous plugs had a hex socket and I took a long hex nut and put one end in the plug and the other end in the socket and it twisted the nut appart. I ended up getting a hardened piece of hex stock that did the trick. Since then I haven't had a problem now that I wrap in teflon tape and have the square type drive type.

Lance
Forget the teflon tape, get some "neversieze" & dope it up. Works better than teflon for these purposes.

88ProStar
10-13-2004, 02:41 PM
Does anyone know what we "should" be using for the hex plugs? I want to winterize myself this year and have no idea what to use to get those plugs out. Thanks!!!

OhioProstar
10-13-2004, 02:53 PM
Should be a torx....maybe JimN knows the size.

Lance
10-13-2004, 03:40 PM
Sears sells a socket with the harden hex insert that is able to get the hex plugs out. I don't remember the size but they have a whole range of sizes. That is what my brother has been using on his. Once I got them out the first time I replaced mine with the kind with square heads so I could just use the ratchet as others have discussed on this board.

I don't think these are the same as torx as they are more star shaped aren't they?

Still have the question though of how often this maintenance should be done.

OhioProstar
10-13-2004, 03:43 PM
I take mine out every year to keep the exhuast manifolds from cracking at the seams. Unless you run a lot of AV through I would suggest it.

JimN
10-13-2004, 04:00 PM
It's just a regular hex - 1/2", I think. If you want to check, put a 1/2" extension or wrench up to it and see if it's the same size.

The plugs should be removed every year during winterization and reinstalled in spring, along with all of the other plugs.

kentsmith12
11-29-2004, 05:34 PM
I got one for you guys...

Just went to winterize my boat '96 Sammy Duval and my exhaust manifold drain plugs were rusted - so much so that I could not get them to unscrew... so much so that one of them broke and two of the sides are gone - so hex screww will not work. The plug is still intact and the manifold is still sealed; however, no way to get out other than drill or replace manifold top. Anybody got some suggestions regarding this?


Thanks.

JimN
11-29-2004, 06:11 PM
You may need to drill it out and use a large bolt extractor. It may break while you're doing this, so the added benefit is that you would be just about done at this point. Make sure you spray some good penetrating oil on the threads a couple of times, a day in advance. I have used PB Blaster for the last 5 years and haven't found anything better. Whatever you use for the plugs after you get these out, wrap them with Teflon tape or use anti-sieze when you install the new ones.

kentsmith12
11-29-2004, 06:18 PM
Thank you - I'll try the PB Blaster first, then drill and extractor - worse case I get new manifolds - any idea how much those cost?

Leroy
11-29-2004, 06:30 PM
JimN; Do you know if a 2001 Maristar with LTR engine has exhaust manifold plugs? I've looked and cannot find. All I can see is use the hoses to drain, along with the knock sensor and the block plug on the other side from the knock sensor.

Thanks!

murphfsu
11-29-2004, 06:36 PM
I was considering removing my exhause manifolds and repainting them this winter. I was hoping to try to get the drain plug removed at that time as well although it looks pretty darn rusted.

Anything to consider when removing the manifolds. I had a new block put in this past summer when one of my valve seats blew on me -- basically the only thing that is not new on my engine are the manifolds.

Any suggestions or considerations when removing the manifolds?

AirJunky
11-29-2004, 07:17 PM
I replaced the plugs in mine with the L & hoses connected like all the newer boats have. No special tool needed & haven't seen must rust since it doesn't sit in there for any length of time.

André
11-29-2004, 09:29 PM
I think peoples have a tendancy to overtight those manifold plugs.
Not much pressure in there...Just a bit of plumbing paste will seal it good without overtighting them.
My .02 cents FWIW!

JimN
11-29-2004, 10:06 PM
Leroy- the hoses and plastic fittings replaced the plugs, due to just about everyone with the plugs having problems with them. Just uncouple the hoses(make sure the water gushes out), pull the knock sensor and the other block plug, pull off the lowest end of the hoses, drain the oil cooler and remove the impeller after stabilizing the gas and fogging it after warming it up. Using anti-freeze is your option.

Lance
11-30-2004, 06:30 AM
I agree with you Andre that these plugs are often over tightened and MasterCraft/Indmar were probably the biggest offenders. Even if these things were to drip a little the water is just going in the bilge where it will be pumped out with all the other water that gets in there from shaft seal, power slides, the countless number of people getting in and out of the water, etc., etc.

jimmer2880
11-30-2004, 07:10 AM
If you remove your plugs every year & don over tighten, you'll probably never have any problems. I remove mine each year & don't use any sealer when I re-install (I know I should).... Never had any problems.

If you're going to re-paint them anyway - you may want to try heat if the PB blaster doesnt' work. Just be warned... wash all the PB Blaster off first. PB Blaster is flamable (pls don't ask me why I know this:uglyhamme )

I've had good luck in other cases where I heated the nut (or whatever the bolt was threaded into) with a torch, then immediately after removing the torch, hitting it with PB Blaster. The act of cooling down seemed to draw the PB Blaster into the threads.

kentsmith12
11-30-2004, 12:46 PM
if I am unsuccessful at getting the plugs out - I will most likely wait until spring and have them drilled out. Until then if I want to put antifreeze in - how should I go about doing this? should I just put in the hose connection at the front of the manifold - I don't normally put anti-freeze into the engine - Texas never gets cold enough for any extended duration - my boat is usually winterized for no longer than 2-3 months. I simply drain the fluids - just in case. Obviously, I still have water in the manifolds - again, until then if I want to put antifreeze in - how should I go about doing this?

Thanks

Kent

AirJunky
11-30-2004, 01:01 PM
You could pull the hoses at the thermostat & fill with antifreeze. Or just open everything up & start the engine. 95% of the water will be blown out. I did this for years in Seattle (learned it from the guys at HO Sports) & we never had problems.

kentsmith12
11-30-2004, 01:38 PM
i fogged the engine - pulled the hoses and dead started it about 4 or 5 times to push everything out. Therefore, I guess I should be OK.

If I wanted to put antifreeze in the hoses attached to the thermostat - where are they located. Are they the hoses that attach to the front of the manifolds?

Thrall
11-30-2004, 02:14 PM
If they're rusted in, heat is the best way, after some good soakingd w/ WD or PB. A propane torch won't do it (probably), but an oxy/acy torch w/ a rosebud or welding tip works good. Don't heat the plug directly, heat the manifold around it. Manifold will expand slightly and enable you to loosen the plug. Get a good fitting hex wrench and don't baby it. Give it the first good smack w/ a hammer if it don't work by hand. This will req repainting the manifold afterwards.

Leroy
11-30-2004, 03:13 PM
Thanks Jim, that was what I did. I can feel the pain of the plugs from this thread.

_JR
12-18-2004, 06:20 PM
Looking for a hex wrench/socket for the exhaust manifold, and it is NOT 1/2".

Anyone have any idea of the size, otherwise I will be ordering a Hex Socket kit for $100 bucks to get this freakin plug out. :eek:

Help!

JimN
12-18-2004, 06:45 PM
Why buy the whole set when you just need one? Next time you see a Snap-On, MAC, MATCO, Cornwell, or? tool truck, see what they have. You should be able to buy one bit. Is the plug flush with the manifold, or does it protrude about 1/4"? If it's out that much, maybe you can grab it with a Channel Lock.

Lance
12-19-2004, 06:48 AM
JR,

I just went in the garage but can't find mine. In one of my previous postes I mentioned that I replaced the original plugs with ones with a square hole so I don't use it anymore. I would hate to see you buy a whole set of hex allen sockets if you don't have a real use for them.

If you have some nuts or bolts of various sizes sistting around stick the heads in the hex hole to find out which one fits then find the size by sticking it in a regular socket. Then you only have to order one.

As I read you post I thougt that I might send you mine since I don't have a need anymore but since I didn't have it in my garage here it must be at the lake and I won't be getting down there for a while with the holidays.

Lance

east tx skier
12-19-2004, 08:05 PM
I'm still wondering where the mongo brass plugs I have in mine came from. I use a set of channel locks to get them off.

JimN
12-19-2004, 08:50 PM
I'm sure someone had the same trouble getting the original ones out and decided that the brass wouldn't rust in place like the other ones. I'm not sure why steel was used for the plugs in the first place. Probably one of those "but it's the way we've always done it" things.

_JR
12-20-2004, 01:39 AM
Why buy the whole set when you just need one? Next time you see a Snap-On, MAC, MATCO, Cornwell, or? tool truck, see what they have. You should be able to buy one bit. Is the plug flush with the manifold, or does it protrude about 1/4"? If it's out that much, maybe you can grab it with a Channel Lock.


JimN -

Agreed, but I live out in the country, so there aren't too many tool trucks rolling around...the reason that I am going to break down and buy them all is that I do not know the size, and I am 30 minutes from town to try and located this part. I have been to half a dozen auto parts stores, Sears, Lowes, Home Depot, etc and can't seem to find a hex wrench or socket larger than 1/2". This is starting to pi$$ me off, so I figured that I would just buy ALL of 'em! :rant:

_JR
12-20-2004, 01:43 AM
JR,

I just went in the garage but can't find mine. In one of my previous postes I mentioned that I replaced the original plugs with ones with a square hole so I don't use it anymore. I would hate to see you buy a whole set of hex allen sockets if you don't have a real use for them.

If you have some nuts or bolts of various sizes sistting around stick the heads in the hex hole to find out which one fits then find the size by sticking it in a regular socket. Then you only have to order one.

As I read you post I thougt that I might send you mine since I don't have a need anymore but since I didn't have it in my garage here it must be at the lake and I won't be getting down there for a while with the holidays.

Lance


Lance -

Thanks for the offer, I think I might just call SkiDim and see if they have "replacement" plugs that use the 1/2" socket to remove. The current plugs are exposed enough that I can get them out with my vise grips, so that may be the easiest (and cheapest!) solution. Every time I think that I have every tool I will need for the boat, here comes another thing I am missing! :(

_JR
12-21-2004, 01:41 AM
FYI, it is a 9/16 hex for the exhaust manifold drain plug.

Ordered one today for $6. Sweet.

kentsmith12
12-22-2004, 01:26 AM
update from my 11/30 post.

I finally got to the lake and used the PB blaster on my manifold plugs and let it sit for 24 hours. I have a hex socket that fits the hex nut perfectly and gave a good beating; however, didn't budge; AT ALL. I keep the boat on lake cypress springs in east texas and temps hardly get very low - except this week should dip below freezing for a few days during the evenings but the days will be above freezing. the engine is winterized less the manifold plugs. I guess i'll get a machine shop to drill them out in the spring. hope my manifolds don't crack...

jimmer2880
12-22-2004, 07:58 AM
update from my 11/30 post.

I finally got to the lake and used the PB blaster on my manifold plugs and let it sit for 24 hours. I have a hex socket that fits the hex nut perfectly and gave a good beating; however, didn't budge; AT ALL. I keep the boat on lake cypress springs in east texas and temps hardly get very low - except this week should dip below freezing for a few days during the evenings but the days will be above freezing. the engine is winterized less the manifold plugs. I guess i'll get a machine shop to drill them out in the spring. hope my manifolds don't crack...
Try Jacobs Brothers brand. It's in a black can with JB 80 on it. My local NAPA stores carry it.

Also - before you go drilling it out, I think I'd hit them with a torch. I've had good luck before getting the nut (in your case, the manifold) good & hot, then remove the torch & hit it with some form of PB blaster. The cooling effect will draw the PB blaster in. Once it cools a little, then try it. You don't want to heat the bolt (in yoru case, the hex screw) also, as you're trying to get the outer of the 2 materials to expand (as metal does when it gets hot) & not the other.

I wouldn't go drilling it out just yet.

Good luck.

jimmer2880
12-22-2004, 08:00 AM
Ohh yea - almost forgot... PB blaster is flammible, so don't spray it on, then hit it with a torch unless you're ready to put out a small fire. (nothing big, just a little flame).

PeteS
12-22-2004, 10:11 AM
I'm in the same exact situation as Kent and JR. The boat is winterized now, and in northern MI -- cold. You CAN get replacement plugs from DIM which are brass and use a 1/2" socket, I just received mine.

Now it's just removing the old ones. Where did you order your 9/16" HEX, JR? Or I may just use the lube, heat, channel lock method to remove.

André
12-22-2004, 10:22 AM
I would bang them hard with a short sledgehammer and some pieces of metal so not to damage the square or hex,just like a harmonic puller on a prop.

PeteS
12-22-2004, 10:26 AM
Interesting approach, Andre. So you are saying just lay a piece of metal between the plug and your hammer, and bang away hoping the vibrations will free the plug? May not be a bad idea. Would this be after the lube and heat?

André
12-22-2004, 10:32 AM
Only lube.hitting the area after heating it would not be a good idea.If not working then heat,then drill.

André
12-22-2004, 10:36 AM
One other thing that i do on stuck bolts is lube ,then try to tighten it,more lube ,try again to remove it.Works often on bolts,not sure on those plugs,may worth a try!

Thrall
12-22-2004, 12:46 PM
Heat's still your best bet. You'll cook some paint off the manifolds, but that's easily repainted. If you don't have access to oxy/acy, but a can of MAPP gas for your propane torch, it gets hotter than propane. Heat the crap out of the manifold, not the plug. Get a breaker bar, or a ratchet you can return if broken, after heating, hit the ratchet w/ a hammer in the loosening direction "poor man's impact wrench". You'll get more breaking torque out of smacking the end of a 12" long ratchet w/ a 2 lb hammer than if you put a 2' long breaker bar on it.

André
12-22-2004, 02:42 PM
Gotta agree with Thrall here,heat is a sure bet but not everyone is at ease getting an open flame in the boat.
I do use Mapp( yellow bottle instead of blue) with a Turbo Torch.You can get things pretty red with this set up!

Always a good thing to have someone close by with a fire extinguisher...In case of a bad luck!

BriEOD
12-22-2004, 03:26 PM
Yeah, or else the next thread we see is in the interior section "holy smokes guys I torched the interior of my boat what do I do now!!" :eek:

Ben
12-29-2004, 03:05 PM
Another good way I've used to remove large fasteners like this is to use an air chisel. The PB is great and a good start. If heat & good leverage don't work, I'd try and impact gun w/the right socket. Use a sears socket so you can get a new one after you trash the 1st one... If that doesn't work, get one of the cheap $15 impact chisels. THey also come with accesory kits when you buy a compressor.

Use a hammer and a cold chisel to make a starting groove, then use the chisel to work the bolt out. YOu want to aim the chisel on one sie of the nut at about a 45 deg angle to the way it needs to rotate. THe impacting action will dig into the plug and hopefully loosen it. You kind of follow the motion of rotation as it loosens. Hard to decscribe via keyboard, hope ya understand.


I've done this on stripped out keyed car wheel lugnuts before, similar size fastener. You can use my tools if you want, I may be close. We're near great lakes mall.

good luck.

kentsmith12
01-07-2005, 01:01 AM
Thanks for the feedback guys; always helpful and great info.- I've got some MAPgas and will try the heat method w/ PB. I'll let you know the results.

If I need to repaint the manifold in black what should I use - brand/type suggestions?

_JR
01-29-2005, 11:30 AM
Pete -

Got the hex wrench from USAHardware.com.
http://www.usahardware.com/inet/shop/item/23600/icn/20-370932/eklind_tool/15136.htm

94PS190
01-29-2005, 05:44 PM
Put your socket in a freezer or cooler while your using the heat. Put cold socket on and chill the plug while the manifold is still hot. Then bang away. Works every time.

jimmer2880
01-31-2005, 07:27 AM
Put your socket in a freezer or cooler while your using the heat. Put cold socket on and chill the plug while the manifold is still hot. Then bang away. Works every time.

Wow - great idea. I never heard that one before. I'm sure i'll be needing that the next time I work on my old 88 Chevy pickup.

atlfootr
01-31-2005, 10:15 AM
Thank God for Outboards ... I use mine YEAR ROUND!