overheat horn - head discolored

[Kevin Burrows]

Sad story. Been waiting for Dad to turn over 1981 Procraft for 10yrs. Got it finally. Drained gas, put fresh in, new battery and started in driveway. Smoked but started good. Telltale hole good flow. Took to lake. Started perfect. Ran for apprx 15-20 minutes at idl, 1/2 throttle everything still great. Ran it up to 3/4 throttle and within 10 secs. the heat horn went off. Shut engine off within 10 seconds. Water was still streaming out of pee hole. Smoke puffed out of cover. Removed cover, starboard cyl heads light brown and sizzled when I spit on it. Port side ok. (they were both white.) Had boat towed to ramp. The details on motor. 1981 Johnson OMC v4 seahorse, 140 hp Model J140TLCIH. The motor has never had a wrench to it. I am very mechanical and would like to attemp repair. I have the sevice manual. The 1981 xs1650 Procraft and Johnson 140 was bought new in 1981 and had not seen water since 1997. I put 100's of hours on the water when I was younger and never had any trouble out of boat or motor. I love the boat and motor and don't want to part with it. Where do I start?

 

[Kevin Burrows]

Re: overheat horn - head discolored

More info: Started engine in driveway today. Cranked up ealily and idled perfect. Starboard (discolored Head) heated up to touch very quikly while the other side stayed warm to touch.

 

[Solittle]

Re: overheat horn - head discolored

Lets start with a compression check. Do it with a guage that screws into the spark plug hole rather than one you push in. Post back the results. All cyl should be within 10% of each other. Also let us know what the plugs look like.<br /><br />If you are lucky there is no major damage. In any case you will need to do the water pump, thermostats, new plugs and change the gear oil. When you do the water pump look out for any pieces that may have come off of the old impeller and gotten stuck somewhere.<br /><br />You may have to rebuild the carbs but let's see what the compression comes up with.

 

[seahorse5]

Re: overheat horn - head discolored

Probably a stuck thermostat or in rare cases, an obstruction in the water outlet area, bugs, mud, etc.<br /><br />It sounds like you ought to find out why the overheat horn did not sound off. Is it rusted away or disconnected somewhere?<br /><br />Since the heads got hot enough to be discolored, replace the head gaskets and the exhaust cover gakets which probably dried out and can burn out easily. At the same time the heads are off, you can inspect the cylinder walls for scoring or aluminum transfer.

 

[rodbolt]

Re: overheat horn - head discolored

hello<br /> sounds like one of the thermostats is stuck or clogged. if one head gets hot and the other does not. a quick test is to remove the hoses from the bottom of the heads and route them overboard start the motor with the hoses off and a flusher or other good source of water and see if the heads heat up and also check for almost equal water flow.but if I were you the first thing I would do is break out the manual, read, heed and belive it. then take off the heads and inspect the cylinders, resurface the heads. I will warrenty if the paint is discolored they are warped beyond the .004" limit. repace the t-stats with a complete kit from all grommets, springs, t-stats and gaskets. then replace the water pump impeller kit<br /> the kit is not that much more in price then just an impeller.<br /> after that it is anybodys guess <br /> oh and if the bolts will come out you may want to replace the exhaust cover gaskets. you will find to access the t-stats with the cover on is almost impossible <br /> takes me about 2 hours to change the t-stats on the bubble back motors if the bolts come out and 1/2 the time I tear at least one gasket while reassembling the pressure springs.

 

[Kevin Burrows]

Re: overheat horn - head discolored

Compression Test Results: Starboard Side (discolored head) Top 90 lb. plug tan-dry, Bottom 139lb. plug blk-wet. Port side top 139lb. blk-wet, bottom 139lb blk-wet. Ok, looks like troble on the starboard top. What next? and thanks for all the reply's. Where can I get parts? I used a mail order for my KDX Kawasaki dirt bike and got everything at wholesale. Anywhere out there that might be cheaper by mail? My plan is to heed all of your advise disassemble get a parts list together, order, and then reassemble. Thanks again.

 

[Hooty]

Re: overheat horn - head discolored

Looks like a boring, new piston and rings for nr. 1.<br />There's a s***load of parts on line. Here's a list another one of the guys here on iboats posted awhile back. Buyin' boat parts now, good luck gettin' 'um wholesale.<br /><br />c/6<br />Hooty<br /><br />Posted by icwebpeople (Member # 13044) on August 13, 2002, 07:13 PM: <br /> <br />Member # 13044 <br /><br />posted August 12, 2002 07:00 PM <br />--------------------------------------------------------------------------------<br />i hope this helps some of you. if you need more help let me know.<br /><br />icwebpeople@aol.com<br /><br />this is a site listing lots of used parts dealers<br /><br /> http://www.marineengine.com/outboard_motors/parts/ <br /><br />try some of these<br />------------------------------------------------<br />you can also try this place. its in australia but ive been told they have everything for older boats and motors.<br /><br /> http://www.goldenseal.com.au/ <br />-------------------------------------------------<br />if it doesnt have a www. in front of it it is an email address ( for example franzmarie is franz marine @aol.com but it also can be reached by www.franzmarine.com) <br /><br />i hope this helps when i put the list together i didnt think about sending out. but im in the prossess of rewriting it for others to understand clearer. if you need help let me know.<br /><br />partsdesk@tenkillermarine.com<br />franzmarine<br />astymegoesbuy200<br />linda@nu-z.net<br />parts@brokeboats.com<br />discount marine weedsport n.y. ask for wayne 315-834-6843<br />www.GLM-marine.com 626-357-0077<br />nicholls marine ltd 905-871-1965<br />nicks marine 859-854-3888 let it ring a while<br />www.americanoutboard.com <br />chesapeak marine 410-286-2520<br /><br />fairwinds@toad.net<br /><br />mtech@mastertechmarine.com<br /><br />discountparts@americanoutboard.comservice@boatmotorrecyclers.com<br /><br />willyo@bellatlantic.net<br />info@outboardexchange.com<br /><br />info@ccomarine.com<br /><br />sales@marineparts.com<br /><br />obparts2@yahoo.com<br />Tsmyth@cfl.rr.com<br /><br />partsdesk@tenkillermarine.com<br />partsform@newagemarineparts.com<br />manualform@newagemarineparts.com<br />charlie@charliesusedparts.com<br />ironman@csweb.net<br />outboard@searnet.com<br /><br /> http://www.nicksmarineoutdoors.com/NicksMarine_Storefront/asp_StoreFront/QuickOrder_Launch.asp <br /> http://www.iboats.com/ <br /> http://www.geocities.com/thechryslercrew/ <br />you can post an add here http://www.hurrikain.com/disc1_index.htm <br />post an add here http://www.iboats.com/cgi-bin/ubb/ultimatebb.cgi <br /> http://www.marineengine.com/outboard_motors/parts/ <br /> http://www.boatowners.com/drives_vdrives.htm <br /> http://www.fairwindsmarina.com/chryslerpage.htm <br /> http://aolsearch.aol.com/dirsearch.adp?knf=1&query=chrysler outboad parts <br /> http://aolsearch.aol.com/dirsearch.adp?knf=1&query=chrysler boat parts <br /><br />--------------------<br />dj<br /><br />--------------------------------------------------------------------------------<br />Posts: 26 | From: md | Registered: Jul 2002 | IP: Logged <br /><br />icwebpeople <br />Captain

 

[93bronco]

Re: overheat horn - head discolored

just curious- have you removed the head to verify that its not just a head gasket?<br />or does the tan dry plug suggest a lean condition with possible piston damage?

 

[Kevin Burrows]

Re: overheat horn - head discolored

2kboat, I will take the head off on tuesday. This should help with the diagnosis. I am hoping it's just the rings, gasket, or something simple. I will post condition of head, piston, etc. after I remove it. I have my fingers crossed. Thanks for the reply. Hey SoLittle what do you think the low pressure on cylinder one could be? Worst case? Best case? Could it be rings only?

 

[Solittle]

Re: overheat horn - head discolored

The low pressure on #1 is probably due to the head gasket. If you are real lucky that will be all. When you get the heads off carefully examine the cylinder walls of all cylinders and the tops of the pistons. Let us know what you find.<br /><br />At a minimum you will need a head gasket set. And take the heads to a machine shop and get them dressed. I replaced the head gaskets on one of mine (I have two 1987 V4s) a couple of weeks ago. It cost $30.00 to get the heads dressed. Make sure that you torque the head bolts correctly (18-20 lbs.) and in the correct sequence - and retorque after running a couple of hours.

 

[Kevin Burrows]

Re: overheat horn - head discolored

ok, the head cover and head is off. It looks like good news. There was complete blockage in the water route. It appears that water was only circulating on the bottom half of the bottom cyl. I went ahead and removed the port side head cover. No blockage and it seemed a bit moist. Now for the cyl. and piston. The cyl wall is not scored or grooved. The top of the pistons are black with soot. How would I know it the head gasket is blown? Would dark/oily spots on the outside of the cyl wall be a clue. There is some but not like I would have expected. by the way I re-tested the cyl compression and it reached 100lb. The gasket came off in one piece and doesn't appear to have any tears or breakthoughs. I really appriciate all of the feedback I'm receiving. Again I am waiting for replies before I continue with the repair.

 

[Kevin Burrows]

Re: overheat horn - head discolored

Oh yea, I almost forgot I have digital photos of everything. I'm not sure if I can or need to post them here. Please advise.

 

[Kevin Burrows]

Re: overheat horn - head discolored

Oh , I almost forgot, I have digital photos of everything. I'm not sure if I can or need to post them here. Please advise.

 

[Solittle]

Re: overheat horn - head discolored

Good so far - See my earlier post on suggestions. At this point I would pull the lower unit and remove the water pump. You are looking for chunks which may have come off of the impeller and went a traveling through the water passages. Might want to pull the t-stat housing while we are at it. You want to back flush everything at this point.<br /><br />I would replace the deflectors in the block also. See your manual if you are not farmiliar with them - cost less than $2.00.<br /><br />Do the t-stats and the pressure thingys while you have the heads off.<br /><br />Get the heads dressed at a machine shop ($30.00) to make sure that the heads are perfectly flat & true.<br /><br />Reassemble everthing with new gaskets & follow the manual for torque value & sequence (18-20 lbs I think). <br /><br />Just a late thought - Lets say you got some crud in one of the carbs causing a lean condition. That can result in a lot of heat that can result in what started this thing. What I'm getting to is if you have gone this far you might want to rebuild the carbs while you are at it to be on the safe side.<br /><br />Let us know the results.

 

[93bronco]

Re: overheat horn - head discolored

while you are doing this it wouldnt hurt to spray fogging oil into & on the suspected piston/rings, incase one of the rings is sticking - it mite help to losen it while doing the other stuff.<br />-<br />if you have the heads done make sure to deburr & clean them good.

 

[rodbolt]

Re: overheat horn - head discolored

hello<br /> sounds like you may get lucky. all the advice you have looks great to me. I would recommend doing the thermostats while the heads are off. it is easier to get to them with the heads off. also remove the aft lower cowl trim to access the springs and such on reassembly.ask your local dealer about any head gasket sealers<br /> I usually coat the gasket periphery with OMC gasket seal or Quicksilver perfect seal as per a recommendation from a service seminar.<br />I glue the tstat housings together with OMC adhesive M and use OMC gasket sealer on the adaptor to housing gasket.<br />good luck and keep the wet side wet

 

[Kevin Burrows]

Re: overheat horn - head discolored

Hapy Ending to the story. found clogged water passage just under head cover. It blocked all water on starboard side. Also the head gasket was blown. Replaced impeller (whole kit)head gasket, head cover gaskets, t-stats, gomets, springs, relief valves plus a few parts I broke during the process. Total cost about $200. Tested it in drive way. Ok, so I took to lake. Broke it in for two hours. Heads only got to about 146. The cylinder block got a little hotter. Hottest I registered was 176. It seemed to run cooler the faster I ran it. The motor ran just like it did in 1980 when my dad bought it. Now little things don't work. Tach goes and comes. Fuel guage doesn't work, and now the trolling motor doesn't work. Ok now that I've put about 12-14 hours in it, I might as well finish it off. Thanks a bunch for all the post. Sincerely Kevin<br />PS that clevis pin to the gear rod was a b****, and so were the springs on the stats.

 

[G DANE]

Re: overheat horn - head discolored

Good to hear kdxrider. <br /><br />You mentioned blocked cooling passages. What did block them ? A piece of the impeller og salt ?

 

[Kevin Burrows]

Re: overheat horn - head discolored

It couldn't be salt because never been in salt water. It was white/tan/gray powdery stuff. It could have been a dirt dobber nest that buned up when engine over heated or just silt from the rivers and lakes I used the boat in. I never flushed it before. I wish I had a definate answer as to what the substance was.