200 Mariner
 

I know it's not hull related but I think I need a new impeller in my Mariner and was wondering if anyone had any links for changing it.
Changed the thermostats and it still only pumps water out top at about 2000rpm. Also seems to come out pulsing.
Thanks
Joe

Re: 200 Mariner
 

its really really easy to do. heres what i do.
i put it in gear and remove all the nuts and bolts holding the lower unit on except the one closest to the transom. that one will hold the LU on for you. get a helper if you need one and loosen that nut. the LU will slide right off. the water pump is very straight forward. replace everything. get the whole kit. it will cost about $50. just when you take off the old piece match them up with the new ones in the kit and put it back the way it was. be careful not to over tighten the bolts holding the pump housing on. when your ready to put the LU back on, get your helper again and line up the shift shaft which should still be in gear and you will have to move the prop a little bit to get the driveshaft to line up with the splines. when it lines up it will slide right back up and put that nut on that you took off last closest to the transom to hold the LU. it probably takes about 20-30 minutes tops.

Re: 200 Mariner
 

Jobu - you should definitely change the impeller. Also understand that merc thermostats won't open until block temp reaches 143 degrees. There is only a minimal tell tale on those motors until the water temp reaches 143 and the tstats open up. You are also in a cold water area, so the tstats react a little slower.

Re: 200 Mariner
 

Well the housing and thermos where covered in corrosion and it looks like the last ones were never cleaned out first so the weren't seated correctly. But what do you think would cause the intermittant pulsing of the water coming out? My guess is a bad blade on impeller. I had it running for a few minutes and the heads were warm to the touch so I am guessing that the thermostats were opening. I will try flushing it all out good again and replacing the hoses too. But I'll also give the impeller a shot too. I was doing this in the driveway with a hose and earmuffs with good pressure(if that matters) and again nothing coming out at top until about 1900-2000 rpm. Thanks Blue too!
joe

Re: 200 Mariner
 

Also BigShrimpin....noticed you were local...WTF!!! is up with this rain? :D

Re: 200 Mariner
 

the heads should be warm but still cool enough where you can keep your hand on them. i dont have t-stats in mine, i will put them one day but im also going to add another temp gauge so i can see both sides of the motor. the heads fill up with water from the bottom up. do you have a psi gauge on the dash?

Re: 200 Mariner
 

No, it's not a missing impeller blade. Even with two adjacent blades missing, you would be unable to detect any pulsing in the flow of water, as the impeller simply rotates too fast.
Pulsing in the flow of the telltale is either thermostat or poppet valve.

Some think I am overly careful, but I replace my impeller every January, or every 100 hours of use, without fail. I advise all of my friends to do the same. Waiting for your water pressure to fall away to nothing before changing the impeller is like waiting for your oil pressure to fall away to nothing before checking or changing your oil. By the time the pressure falls, damage may already be occurring.

$18 for a new impeller is a cheap insurance policy. I have never lost an engine or powerhead to overheating in 41 years of boating, including over a decade in marina management. On the other hand, I have seen LOTS of outboard failures caused by NOT changing the impeller regularly.

I also have a mechanical water pressure gauge, even though my Optimax Smartcraft system has an alarm if the water pressure falls below 6 lbs.

Bottom line: change the impeller, change the thermostats, change the poppet valves. It's the right thing to do.

Re: 200 Mariner
 

All the above is good advice. I would add just one thing. If you're going to work on your Mariner yourself, buy the FACTORY service manual, not a Seloc or other after market manual. The factory service manual will give you step by step instructions for changing the water pump, cleaning the carbs, pulling the power head, and everything in between. You can usually pick them up on ebay for about 20 bucks.
Dave

Re: 200 Mariner
 

Sorry for taking so long to respond but it's been non-stop rain here and the boat has been on the back burner for a while. That said, I changed the thermostats and was still getting similar results. But when I run it with the thermostats out it really flows good (and I have hardly no water pressure at my house)
The poppit valve...is this also called a diaphram?
I bought one from the local Merc dealer and he gave me a schimatic...looks like the lower right bank of block. But there is also an electrical panel there...stupid question but does this have to come off first...and also is this the poppit valve?
Also, thanks to everyone who has responded...I haven't been on in a while and forgot how helpful everyone here is!
Thanks,
Joe

Re: 200 Mariner
 

Okay...here's the status.
New stats...same thing...low to no pressure out of top tell tale at idle.
New poppet valve....same thing(there was some seaweed...also I put the round plastic disc that goes between the valve and screw convex side pointing in?).
Drop the LU redo the impeller, gaskets, housing exactly...put key back in...line up LU and reinstall with minimum difficulty...Now I get NO water out of all three...I assume that I didn't line up the water pipe correctly...I try it again and get no water still. Is there a trick to lining up the guide for the copper pipe? Does the pipe attach first to the upper part or to the pump housing first...also if anyone can explain the order this would be great. Also I cant see it but it looked like I got it lined up right so maybe something completely different. If anyone can help it would be greatly appreciated.
Thanks Joe :D

Re: 200 Mariner
 

Joe there should have been a little plastic tube guide included with that kit. It helps line up the top of the water pump . . . so that the copper tube can slide into the correct place and seat into the rubber grommet. You need two people to do this job or a ratcheting tie down to hold the lower into place.

Re: 200 Mariner
 

So the rubber grommit goes in the housing then the plastic guide goes into that(tightly) and when you slide in the unit the copper pipe(already attached to the upper drive housing)slides into the plastic guide pipe and eventually into the rubber grommit and housing?
Thants how i thought it worked...but must not have gone right...is that right? also I did get a new white pipe but didn't see new rubber grommit?
thanx Bigshrimpin...Im still up
joe

Re: 200 Mariner
 

I have seen Great instructions here, Just a question tho, as you bolted the water pump housing to the LU did you rotate the shaft so the impeller is free?

Re: 200 Mariner
 

A few thoughts:

The new water pump housing probably already has the rubber bushing installed, so all you need to do is place the alignment tube and the pipe will seat properly.

Also, did you turn the drive shaft clockwise (looking down from the top) when you seated the impeller in the housing? If you turned counter clockwise, it may not pump.

And did you remember to place the key on the flat spot in the driveshaft before dropping the impeller down the shaft? Without the key, the impeller ain't going to turn.

And I reiterate my recommendation to pick up a Merc shop manual. All things are clear when you've got the book.

Good Luck,
Dave

Re: 200 Mariner
 

After the third try,I eventually got everything right with the key and the pipe inlet. Also the impeller was in right and shaft turned clockwise. Now I'm getting water...not steady though. Screw it, it's sunny I'm going in. I dropped her in Plymouth harbor and ran it around at idlw to 1000rpm and it seemed fine. As soon as I got into the channel and got up to about 3000rpm...beeeeeep! the alarm went off.
I later pulled and dropped her off at the boat yard. The mechanic said it looked like the pipe was not seated correctly at the top end . They had it running in a barrel and seemed to be pumping better but still intermittant at idle but pretty steady at 2000-2500. With my hand on the head at 2500 it was actually cool...but when we idled it for a while it got up to 135'F then it looked like the thermos would open and would drop to 119'F.
Not totally convinced but she's going in as soon as it stops raining. Maybe tomorrow or Thurday.
Fingers are crossed and a report will follow.
Any more ideas welcome....the only thing I can think is that there is something floating around in one of the lines???
Thanks for the all support,
Joe

Re: 200 Mariner
 

It sounds like it's running perfectly. Those blackmax motors run hot compared to others and what you describe is "normal" based upon my experience with them. I love those motors.

http://www.wellcraftv20.com/gallery/...669_Medium.jpg

Re: 200 Mariner
 

and it shows.
i need a collection of motor parts like that.

Re: 200 Mariner
 

I feel better knowing that someone who has expirience thinks she's running normal.
I just wish I was getting a more steady stream out of the top telltale. Warm at idle and cool under revs is where I am now and hopefully that's it cause she's going back in on Friday...fingers crossed.
Thanks for the help and advice.
Joe

Re: 200 Mariner
 

Joe - I've run my motor with snipped tstats (washers) and that'll give you the steady pee stream you're looking for . . . problem is that your motor will run cold. If you are north of the cape, you want to run with tstats in b/c your plugs will have a tendency to foul quickly.

Re: 200 Mariner
 

Well, ran it yesterday and it is still spitting intermittantly...but not overheating. But when I ran it up it was rough early then would get over 4800 rpm. Changed fuel filter and water seperator and still topped at 48-4900 rpm not 5600 as it usually does. I talked to the mechanic and he seemed to think it might have a blown head gasket or O ring. He thinks its blowing air exhaust into the water jackets which is causing the pulse. There was also alot of water coming out of the upper exhaust below the upper tell tale. It looks like something I could handle myself so I will give it a shot on tuesday or at least open it up and see. I remember the last day I had it out last year...I was wailing on it with a three man tube and it wasn't running all that good then. He happened to have a similer motor apart and the heads look somewhat accessable.
Does any of this sound like it might make sense?
I have literally gone through the entire cooling system at this point and it all looks normal. Starting to really lose patience.
Joe

Re: 200 Mariner
 

Joe - Focus on what's changed since the motor last hit 5600 rpm. How much water is coming out the oval exhaust ports? If it's just spitting a little water out . . . that is totally normal behavior. O-ring heads came out on the 2.5L in 2001/2002 after mercury stopped producing Mariner. if you are worried about blown headgasket or water coming in . . . check the plugs and see if any look steam cleaned (like brand new). That's one of the signs of a blown headgasket . . . also check for low compression (on one or more cylinders same side).

Personally I think problem without knowing anything about the motor could be a lose plug wire, bad coil, etc. causing one cylinder not to fire (or fire intermittently). Get a spark tester and figure out if one cylinder isn't firing.

http://www.slickbiker.com/Slickbiker...lug-tester.jpg

No offense but that mechanic seems to be overlooking some obvious details and jumping into some pricey "unrelated" repairs. For a good referral you can ask on www.screamandfly.com for someone in the area that knows your motor.

Re: 200 Mariner
 

Big difference between a mechanic and a parts changer - parts changers get very expensive since its your money.

Re: 200 Mariner
 

Again, Thank you. I will get a compression gauge and spark tester. I noticed what looks like some silicone between one of the boots and plug wires...looks like a fix. The comp test should tell me if the gasket is blown too. I looked quickly at the site you linked and will start a thread on my problems later. The mechanic i saw is just a local and not sure he's really intune with OBs, my friend has had a lot of probs with him and started to take his Yamaha's to Weymouth. He's convienient and reasonable. I'm a self employed carpenter and times are a little tough to be fixing what he thinks the problem is. But I am really getting to know my way around this engine...at least that's one positive thing!
Will keep you guys posted...thanks again,
Joe

Re: 200 Mariner
 

Jobu - Even though it's frustrating . . . My advice is to get a manual (I have an extra one) and beat your head against the wall to figure out your problem. Those motors are great!! They are strong, light, easy to work on, and relatively fuel efficient for a two stroke. Also If you need any parts for that motor, I have a garage full of them.

If you want to come swing by my place I can loan you a factory service manual for your motor.

I imagine Monihans Marine is the place that you are refering too. One of the mechanics there when I had a Yamaha 200 was awesome and extremely helpful and generous with his time!!

Re: 200 Mariner
 

I'm going down tomorrow to try a compression test. I couldn't find a spark tester but will look on the way down. If I cant get the revs up I will pull it and take it to Bill's in Hingham, he's at least certified and deals 'em.
I appreciate it on the manual and I will try to track one down. Factory manuals are hard to find but seem invaluable...have a Seloc and it sucks.
I'll let you know and thanks.
Joe

Re: 200 Mariner
 

Finally got a chance to get out to "Victoria's Seacrate" on Sunday and I changed the plug wires. While doing so I checked the plugs and sure enough the top port plug looked brand new. I also noticed the engine had a stronger fuel smell around it. The funny thing is that the tell tale seems to now be spitting almost perfectly. I am heading to Bill's Outboard this morning to get a gasket set but first I will check the spark and compression. I couldn't find a decent tester at either Sears or Pepboys (I like the one BigShrimpin showed in his post).Also the top starboard plug didn't look to dirty either but did seem to have a reddish color to it. When I ran it out of the water , it seemed to have alot of water coming out of the prop hub...is that normal? If it is the head gaskets I think it's something I can handle myself. But I'm hoping it could be a bad coil or even a plug.
Will post later if I can get anything done on her today.
Joe

Re: 200 Mariner
 

Here are my results.
cold comp test
top to bottom port 94, 101, 103 psi
top to bottom strbrd 93, 102, 104 psi
head gasket?
out of ideas.
all six cylndrs have spark...top port plug is cleaner than rest but shows some sign of ignition.
???
Joe

Re: 200 Mariner head
 

The gasket looked frayed around the cylinder opening (new gasket has a metal ring but old one was tattered/ jagged around all openings also I see no metal left). There was a little bit or corrosion/salt between the water jacket opening and the top cylinder.
Also signs of salt inside the head walls...normal?
The top piston has some minor scratches dings in it as does the head in chamber. I'm thinking when the ring disintergated it got chewed up in the combustion chamber...?
As far as I can tell the cylinder walls look scratch free. Pistons have alot of carbon soot but other than the dings they look to be in tact...not new but decent.

Going to put it back together and have a look at the starboard side.

thanks for the info...I listen to it all.
Joe

Re: 200 Mariner head
 

Ouch!! The motor sounds like it may have been apart before . . . . Those compression numbers are NOT good for that motor. Healthy 2.4L and 2.5L 200 mercs/mariners will have roughly 125psi in each hole. Below 100psi is tear down time. Those head gaskets sound terrible . . . I have never seen gaskets blown as badly as you describe. Water (especially saltwater) entering the combustion chamber on any engine is VERY VERY bad . . . If the cylinder walls aren't scored . . . try replacing the head gasket and do another compression test (maybe even another gage). Make sure you use a good torque wrench and follow the instructions in the manual for torquing the head bolts . . . There is a pattern and procedure that should be followed. If you are back close to 120 - 125psi with the new head gaskets . . . then run it and get fuel through the motor.

Are any of the cylinder walls steel? or are they all still original chrome?

If you have any pics post them . . . locater pins can work themselves out and cause damage you describe, but they will score the cylinder walls.

Re: 200 Mariner head
 

Sorry for the late response...And thanks for your help. I feel like Luke Skywalker and you're Obi Wan Kanobi helping my mind mend.
Anyway the gaskets were pretty bad and the top strbrd piston looks like it has some damage. About an 1/8" is dissintergrated from about 1 1/2" of the circumference of the face edge. It looks like it may have siezed a while back and left a little piston on the cyliner wall. But the funny thing is that the cylinder walls look pretty clean, some very feint scores, almost less than the thickness of a hair.
The walls "(Are any of the cylinder walls steel? or are they all still original chrome?)" are definately not chrome and if I had to guess I would say there is less that 1/32" space all the way round the piston.
I haven't had time or energy after work to do anything but I will do a comp test this afternoon.
I followed the mfg specs on torqueing and seems to be ok 30 lbs. in X pattern.
This boat actually came from your neck of the woods. Was Called 'Summer C's' white hull red letters 23 scepter. I bought it from Nauset Marine.
At this stage time and money is running out so I'm gonna put her in and hope she'll at least plane off and get me a few miles to the bass/flounder and have the block pulled in the fall and take it home and try a rebuild.
What do you think? or cheaper to save up for a rebuilt power head....What kind of numbers would you say that would run...if you know?
Any way I'll keep checking for your reply and keep you up on it...right now going to fix my roof and get some bottom paint on the old girl.
Thanks again,
Joe
I will try to send you some pics too

Re: 200 Mariner head
 

Jobu - Have you done a compression test yet?

If your motor has steel sleeves, then it's been rebuilt. 2.4L 200's were all chrome bore motors from the factory.
If it has a rebuilt powerhead . . . it's possible that they dropped on a 2.5L powerhead.

The scoring or aluminum transfer is disturbing and it's likely the ring on that piston is stuck or that the motor got really HOT at one time. If you can catch your fingernail on any of the scratches/grooves . . . that's not good and you want to tear down that motor.

Steel:

http://www.wellcraftv20.com/gallery/...2_4L_steel.jpg


Chrome:
http://www.wellcraftv20.com/gallery/...7/mvc_002f.jpg


2.5L Motor: (notice the behind the liner porting.

http://www.wellcraftv20.com/gallery/...d_Slot_001.jpg

Re: 200 Mariner head
 

I still haven't done a compression test. Maybe tonight if it cools off out there.
My motor is a 2.5 liter...so it would come from the factory with steel lined cylinders? Mine look like your top photo.
I will try to send you a message with two pics of some nipple valves? that were'nt hooked up.
If I have time this weekend I am going to put her back in. I think my best move from hear is to write this summer off if it still doesn't run well and save up for rebuilt power head over the winter.
Joe

Re: 200 Mariner head
 

JobU - The top photo is a 2.4L, but the pics you sent me yesterday are 2.5L powerhead. The pics you sent me with the Oil injection check valve and thermal air valve ( hoses goes to carbs from starboard side head) . . . There are no missing hoses in those pics (well somtimes there is a small 6" section of hose on the 2psi check valve that goes to no where). Hope this helps.

http://continuouswave.com/whaler/ref...Injection.html