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billandsandie
09-27-2013, 09:02 AM
Has anyone ever broken the exhaust manifold drain plug. I have a 1997 w/LT1 and I was very
surprised to see plastic drain plugs where you use a 1/2 inch drive ratchet to remove the plug. I broke mine as soon as I put a little pressure on them. Would love to know an easy way to
remove them and replace with a steel or brass plug.

mikeg205
09-27-2013, 09:17 AM
feed your MCOCD - ;)

http://www.skidim.com/prodinfo.asp?number=MCM000

and it doesn't have to be that tight...

billandsandie
09-27-2013, 09:19 AM
I still need to remove the plastic plugs. I have tried a couple things but no luck any ideas ?

mikeg205
09-27-2013, 09:20 AM
I still need to remove the plastic plugs. I have tried a couple things but no luck any ideas ?

warm them up and pry out -- gently

billandsandie
09-27-2013, 09:25 AM
With the heat from the engine running or blow drier or small torch ?

mikeg205
09-27-2013, 09:31 AM
With the heat from the engine running or blow drier or small torch ?

I would use a heat gun.... small torch - too many things too close to damage.

billandsandie
09-27-2013, 09:51 AM
Thanks Mike

TallSkinnyGuy
11-01-2013, 08:05 PM
I have the same problem on my boat (which I purchased two months ago -- so this is my first winterization). I tried heating the plugs with a hair dryer today, but that plastic is pretty thick and it seemed to barely warm them. Will a heat gun really get them warm enough to be able to pry them out? Any other options?

Cloaked
11-01-2013, 08:15 PM
I have the same problem on my boat (which I purchased two months ago -- so this is my first winterization). I tried heating the plugs with a hair dryer today, but that plastic is pretty thick and it seemed to barely warm them. Will a heat gun really get them warm enough to be able to pry them out? Any other options? ...........................

.

Footin
11-01-2013, 08:16 PM
Replace with brass 1/4 turn ball valves.........done

TallSkinnyGuy
11-01-2013, 08:32 PM
Replace with brass 1/4 turn ball valves.........done

I want to replace them. Gotta get the old ones out first.

88 PS190
11-02-2013, 02:58 PM
I have the same problem on my boat (which I purchased two months ago -- so this is my first winterization). I tried heating the plugs with a hair dryer today, but that plastic is pretty thick and it seemed to barely warm them. Will a heat gun really get them warm enough to be able to pry them out? Any other options?

Hair dryers are not anything near heat guns.

Hair dryers blow dry blondes.... heat guns light wood on fire.

WA Nautique
11-05-2013, 03:17 PM
I drilled out the corners of the 1/2 square recess with a small drill bit, then punched the center out of the steel plugs I had a couple of years ago. once the recess is a square hole, you'll be able to get the rachet back into the hole. Use heat, then turn.

jgraham37128
11-05-2013, 04:27 PM
I have the same problem on my boat (which I purchased two months ago -- so this is my first winterization). I tried heating the plugs with a hair dryer today, but that plastic is pretty thick and it seemed to barely warm them. Will a heat gun really get them warm enough to be able to pry them out? Any other options?

A heat gun will melt them off if needed. They get very HOT!

TallSkinnyGuy
11-06-2013, 10:41 AM
I drilled out the corners of the 1/2 square recess with a small drill bit, then punched the center out of the steel plugs I had a couple of years ago. once the recess is a square hole, you'll be able to get the rachet back into the hole. Use heat, then turn.

I read somewhere that people have used a PVC nipple extractor (same concept as an easy-out, but specific to plastic) and was going to try that yesterday. However, I found that I couldn't get the drill lined up properly because of the big exhaust manifold tubes. I tried but could not get them off and then later read on this forum that it is very difficult to get them off without removing the riser.

What was your trick for getting access to the plug with your drill?

I am planning on trying the heat gun next, but the nipple extractor sounded easier before running into the access problem.

Kyle
11-06-2013, 01:41 PM
I would take a chisel and a hammer and try to back them out by tapping it in the reverse way. If that doesn't work bust it out of there and get the pieces out if the manifold. Melt it out, cut it out, break it out, twist it out, the plastic will not hurt the manifold and heating it won't hurt it either.

If the drain hole threads are rusty then run a tap in the manifold. It is 3/4" standard pipe thread. Run a tap in and back out. You should be fine.

Rat's girlfriend has a '98 205. One of her manifold inlets snapped off and the drain had an issue as well. I used a chisel and broke them out, went to ace hardware, replaced with brass fittings on both inlet and drain for both manifolds.

prostar205er
11-06-2013, 01:55 PM
I had some rusty drain holes in mine (each year the rust would come further out so the plugs weren't getting in far enough to hold). Cloaked suggested running a tap after letting it soak a bit with some PB Blaster. Worked like a charm. Good as new!

TallSkinnyGuy
11-14-2013, 09:06 PM
So I took a heat gun to the plastic drain plugs today. Got them pretty warm but I still had trouble due to the riser downturn and exhaust hose being in the way. Is it fairly easy to take off the four hex-head bolts and remove the riser so I have better access to the plugs? Would I potentially be opening another can of worms?

If the riser and exhaust hose were not in the way I could then also drill a hole in the plugs and use an easy out tool to extract them. I'm not at all experienced working on engines and I am therefore concerned about causing more problems if I remove the risers, but it sure would improve access to those manifold drain plugs.

Cloaked
11-14-2013, 09:14 PM
So I took a heat gun to the plastic drain plugs today. Got them pretty warm but I still had trouble due to the riser downturn and exhaust hose being in the way. Is it fairly easy to take off the four hex-head bolts and remove the riser so I have better access to the plugs? Would I potentially be opening another can of worms?

If the riser and exhaust hose were not in the way I could then also drill a hole in the plugs and use an easy out tool to extract them. I'm not at all experienced working on engines and I am therefore concerned about causing more problems if I remove the risers, but it sure would improve access to those manifold drain plugs.Have you considered using a bare hack saw blade to run up in there and cut them from the inside out? You have drilled the holes on the plug, correct?

Removing the riser(s) is an easy task. If you encounter close quarters on the bolt heads; for an allen head - saw an allen head wrench shorter (on the short side) and it will fit. For hex bolt, grind an old box end wrench down on one side and it will fit. You'll also need two new gaskets. No big deal.

If you remove the risers, consider replacing your exhaust hoses too. They are really easy to replace with the risers off. Look on the inside of the exhaust hoses for deterioration. It happens.

I'd saw those plastic plugs from the inside and knock them out. ?????? I hope I am understanding your scenario with this issue.

.

TallSkinnyGuy
11-14-2013, 10:38 PM
I don't have holes in the plugs yet because there is not enough room to get a drill properly positioned. With the risers and exhaust hoses out of the way I could drill them, but I don't want to remove the risers if that could cause yet another set of repairs or significant challenges.

So it sounds like the risers should come off easily and then I would need to replace the gaskets and potentially the bolts? This is the gasket I would need for my '97 Indmar 350 TBI, right?: http://www.skidim.com/prodinfo.asp?number=OSC992-G

Does skidim sell manifold drain plugs, too? I can't seem to find them.

mikeg205
11-14-2013, 10:53 PM
They are easy to remove if they are not seized up. you will need some new riser gaskets. The easiest thing to do is cut down the allen wrench to fit the 4 bolts that are inset in the risers. You'll also want a hose removal tool to break loose the hoses. My risers and manifolds are 18 years old so I inspect every year. takes about 30 minutes total.

sethro
11-15-2013, 08:26 AM
but I don't want to remove the risers if that could cause yet another set of repairs or significant challenges.

You very well could be facing further challenges. My buddy with his 79 Stars and Stripes just went through this. It started with a leaky riser gasket, no actual leak, just the evidence of a leak once in a while that is on most boats...especially after 10 years or so. I suggested not to worry about it, but one thing led to another, a very long story and many headaches later, it would have been better to leave it be.

I think you can get those plugs out without removing the risers. Drill an off center hole if needed, and maybe get a coping saw blade in there. Don't need a very big hole for oneo of those.

mikeg205
11-15-2013, 08:49 AM
You very well could be facing further challenges. My buddy with his 79 Stars and Stripes just went through this. It started with a leaky riser gasket, no actual leak, just the evidence of a leak once in a while that is on most boats...especially after 10 years or so. I suggested not to worry about it, but one thing led to another, a very long story and many headaches later, it would have been better to leave it be.

I think you can get those plugs out without removing the risers. Drill an off center hole if needed, and maybe get a coping saw blade in there. Don't need a very big hole for oneo of those.

Going to have to disagree with Sethro - Properly maintained risers and manifolds critical to long term engine health. If water seeping into bolt holes you could have other issues. leaky risers outsides usually means leaky inside (but not always) water intrusion into cylinder head bad and leads to hydro-locking.

Lumbergh
11-15-2013, 12:17 PM
I had a seized manifold drain on mine when I bought it.

Removed the riser and manifold, took to machine shop and they got the seized drain out and re-tapped threads. New brass 3/4 NPT plug and some teflon tape, GTG.

You will need a new manifold gasket and riser gasket. There is an Indmar kit sold that has a new gasket and new riser bolts.

Skidim sells a manifold install kit that is quite inexpensive as well, it comes with new manifold bolts, front plastic plug, rear steel plug and gasket.

Simple work for the off season. I put all new hardware on both sides, it's cheap and most boats hardware for the manifolds and risers is original and probably a bit corroded if not outright rusty.

YMMV, how far does your MCOCD go?

sethro
11-15-2013, 08:54 PM
I couldn't agree more that a properly functioning/maintained manifold and riser is critical to engine health. I'm talking about evidence of a minor gasket leak like this pic which was taken from the engine compartment thread. Never could see water coming out, but it was obvious that it did at one time. Don't think that indicates a problem inside the manifold or riser.

About 10 years ago, my OEM plastic plug broke. I drilled an off center hole large enough to get a coping saw blade in there. Then i cut the plug, tapped the threads, and put a new plug in it.

WA Nautique
11-19-2013, 07:42 PM
been a while since I looked at this thread, sorry for the late response.... I had my manifold off at the time, but I would suggest that a snake drill or a 90 drill adapter would get you in that tight spot without taking the manifold off. While I am not much of a fan of Harbor freight cheap tools, this might be a good solution for little money on a one or two time use item. Since your drain plug is plastic, I think the coping saw Idea mentioned above would work well also

mikeg205
11-19-2013, 11:18 PM
I couldn't agree more that a properly functioning/maintained manifold and riser is critical to engine health. I'm talking about evidence of a minor gasket leak like this pic which was taken from the engine compartment thread. Never could see water coming out, but it was obvious that it did at one time. Don't think that indicates a problem inside the manifold or riser.

About 10 years ago, my OEM plastic plug broke. I drilled an off center hole large enough to get a coping saw blade in there. Then i cut the plug, tapped the threads, and put a new plug in it.

Nice motor Sethro - :) polished up that cover did ya... ;)

FWIW - leak outside - leak inside.. just sayin....

TallSkinnyGuy
11-29-2013, 03:43 PM
I was able to get back to this today and ultimately used Sethro's system. I drilled holes and used a coping saw blade and a chisel to make the plug very thin on one side. I then heated it up with a heat gun for a few minutes and was able to break a section of the plug which then allowed it to twist out easily with pliers.

I wanted to get the plug as thin as possible in one section so that it would break/tear easily when heated, but this desire unfortunately got me too close to the threads and I knocked down the threads a bit in a line about 0.5mm wide. However, the front couple threads are okay so I am hoping I can still get a good enough seal with the new plugs to keep the water contained.

The threads are really rusty, so I am in search of a tap and will ultimately spray them with PB Blaster, scrub them a bit with a wire brush and then use the tap for a final thread cleaning. Hopefully that will restore enough order to make it work as designed.

mikeg205
11-29-2013, 04:01 PM
I was able to get back to this today and ultimately used Sethro's system. I drilled holes and used a coping saw blade and a chisel to make the plug very thin on one side. I then heated it up with a heat gun for a few minutes and was able to break a section of the plug which then allowed it to twist out easily with pliers.

I wanted to get the plug as thin as possible in one section so that it would break/tear easily when heated, but this desire unfortunately got me too close to the threads and I knocked down the threads a bit in a line about 0.5mm wide. However, the front couple threads are okay so I am hoping I can still get a good enough seal with the new plugs to keep the water contained.

The threads are really rusty, so I am in search of a tap and will ultimately spray them with PB Blaster, scrub them a bit with a wire brush and then use the tap for a final thread cleaning. Hopefully that will restore enough order to make it work as designed.

3/4 NPT I believe, chase the threads...keep 'em lubed up going forward - all will be good.

sethro
11-29-2013, 06:40 PM
Nice motor Sethro - :) polished up that cover did ya... ;)

FWIW - leak outside - leak inside.. just sayin....

It isn't my engine, it's one from the engine compartment thread. I think it's Kyle's if I remember correctly. :)