Introduction/What and how to check out new to me 1998 Challenger 1800

[OutkastBoss]

Hello I have been reading threads in here all night, lol. My family is looking at getting our first boat and this seems to be the place I want to be!

For a little background on me I always obsess and research as much as I can and try and find good deals on items or save money by learning to work on them myself. Forums like this have always been my go to for research and community. The last obsession was triggered by me buying a Jeep XJ ten years ago and I am currently an Admin and elected B.o.d. member of that forum based club! In that time I learned not only to work on cars but modify and fabricate/weld custom tubework and other parts. Point being with some guidance from this great forum I would like to start my new obsession and learn as much as I am capable about this!

I grew up in the woods so four wheeling fit right in and my Fiance has taken part and followed me all over the country doing awesome trails. But she was raised out on a lake and wants to share that with our daughter and I. She had Seadoos and boats but as a young teen all she wanted was a Seadoo Boat.

We have a deal set up to go buy her dream boat this weekend, it is a 1998 Challenger 1800 in what appears to be great condition for $6,000. The seller is meeting us at a lake and letting us see it out of water. He is also launching it to take us on a test ride and helping us load it back on the trailer. Neither of us have any experience launching or retrieving boats so that will be educational.

My question(s) what should I check while it is out of the water, what should I check while it is out on the water. How do I check the wear rings (etc)? I am driving 4 hours and wont be able to get it inspected by a shop until after I get it home. Because of that do I need to check compression? I haven't done that before, would it be the same tool/procedure that would be used on a car?

Here is the original ad, the owner has been VERY nice and has promised to not entertain other offers unless we back out this weekend.
https://bloomington.craigslist.org/boa/d/seadoo-challenger-jet-boat/6218483994.html

Hopefully it all goes smoothly and we will be fellow owners soon! Then I will post up about finding matching bimini top, towable cover, drain plug Leds, bumpers, jackets, ropes, and tubes!

 

[XP 787]

Very clean boat. Looks like owners took very good care of it. Compression check is a must,and should be around 150psi. Shut boat down in water after test ride and let it sit for at least 15 mins and make sure it starts right back up in water. Let us know how you make out.

 

[mobilefleet]

looks like the electrical has been modded on that boat, I see 2 separate electrical boxes and that isn't stock, it should have one mpem that runs both motors. Just to beware, that will mean no neutral safety so it can start in gear, and also wont have reverse or neutral rev limiter so be very careful who drives and backs up the boat!

 

[OutkastBoss]

Very clean boat. Looks like owners took very good care of it. Compression check is a must,and should be around 150psi. Shut boat down in water after test ride and let it sit for at least 15 mins and make sure it starts right back up in water. Let us know how you make out.

So if 150 psi is ideal and the motors have some age on them, will a slightly lower compression be acceptable as normal engine wear, and if so when is it "too low". Also if compression is low on one or more cylinder does that mean rebuilding the top end or swapping in a rebuilt is in the near future? If so do you happen to know a rough estimate on a top end rebuild or the cost of a rebuilt from a company with a decent reputation and price?

As far as compression testing procedure do you simply pull the plug wires and replace the cylinder you are testings plug with the tester and crank the engine a few times? Is it important to have plugs on all other cylinders of testing motor? Should this check be done on a "cold" motor?

If we let it warm up and shut it down for 15 minutes only to have it not start back up, what is that indicative of? I know on my Jeeps we can get "heat soak" that causes misfires by heating the fuel rail and injectors causing fuel to vaporize. Would it also be indicative of a cooling issue on this craft, carburetor issue or possibly something more serious? (my jeeps are 2000+ so I know very little about carburetors) I did a brief search and saw something about a temp sensor issue but wasn't sure if it was applicable to this model boat/motors.

looks like the electrical has been modded on that boat, I see 2 separate electrical boxes and that isn't stock, it should have one mpem that runs both motors. Just to beware, that will mean no neutral safety so it can start in gear, and also wont have reverse or neutral rev limiter so be very careful who drives and backs up the boat!

That concerns me and begs a few questions. I guess it shows they knew enough to get it running mpem is the ignition module right? I had seen that they go out and can be kind of pricey maybe. Having two possibly fail doesn't sound appealing.

If i understand your post this will cause it to be able to be started in gear and possibly take off?. If the rev limit on neutral is now inactive does that mean you can rev up the motors in neutral and just drive it basically since they do move in neutral some? The cover that comes down to redirect flow for reverse is probably protected by the rev limiter correct? I could see that getting blown off if some knucklehead went full throttle.

Outside of changing the safety of possibly unexpected maneuvering could the lack of a rev limiter cause engine or other drive issues or wear. This kind of makes me want to wait and find another boat. not much in our price range within 400 miles that I found on search tempest though.

Thanks for the help and advice guys!

 

[dmiles]

Not to disagree, because I am certainly no expert on these boats. But I have a 1999 Challenger that has 2 boxes as well, and that appears to agree with the picture in the shop manual. If we are talking about the same items in the picture, the shop manual identifies those as electrical boxes. There are only 2 spark plug connectors, and 2 grounding posts on each one.

 

[OutkastBoss]

Not to disagree, because I am certainly no expert on these boats. But I have a 1999 Challenger that has 2 boxes as well, and that appears to agree with the picture in the shop manual. If we are talking about the same items in the picture, the shop manual identifies those as electrical boxes. There are only 2 spark plug connectors, and 2 grounding posts on each one.

I tried to thumbs up your post but it kind of looks like it shows a thumbs down? I'm new here lol.

Anyways I hope you are right we were pretty excited about this one and haven't had much luck today finding others to go look at. I guess I will be able to tell if the boat has limited rpms in Neutral and Reverse during the test drive. Thanks for posting I was considering cancelling our test ride as it is 8hrs round trip.

 

[XP 787]

Those 2 boxes each hold a coil for each engine. There is supposed to be 2. I have a twin 787 Speedster and I have 2 eboxes. Mine are at a different location though but they are there.

 

[dmiles]

I tried to thumbs up your post but it kind of looks like it shows a thumbs down? I'm new here lol.

Anyways I hope you are right we were pretty excited about this one and haven't had much luck today finding others to go look at. I guess I will be able to tell if the boat has limited rpms in Neutral and Reverse during the test drive. Thanks for posting I was considering cancelling our test ride as it is 8hrs round trip.

That's why I posted. That's a beautiful boat, that looks like it was well maintained. If it's within your budget, I'd hate to see you miss out. I really like that bow seat insert, I've never seen that on any Challenger I've seen, and I don't have one either.

Like I said, if we are talking about the same items in the picture, I don't see how it could work with just one. Also, from what I've read, a boat that has been modified to use 2 Mpem's would need 2 keys. I would think that a boat that had been that heavily modified would be few and far between, and the modification would be very obvious. And just FYI, I just tried to start mine in gear, and it beeped, just like it is supposed to do.

One more thing to throw in the mix, since you will be travelling so far. I had a four hour drive each way myself when I bought mine. I also own an RV, so I am very aware of tires needing to be replaced due to age. Against my better judgment, I made the 4 hour drive with the existing trailer tires. 25 miles from home, one of the tires just came apart while we were heading down the highway. If I had it to do over again, I would have brought new trailer tires with me, and changed them while the boat was still in the water.

From the looks of the boat, I'd say the current owner has kept fresh tires on the trailer as well. I would definitely ask him about it. You can get these 13 inch tires and wheels together cheap as dirt on Amazon, and they seem to be very high quality. Also, there is a chance the current owner has a spare mounted on the trailer. I purchased a mount and a spare tire on Amazon as well. You need a special mount that slants the spare tire, because a straight one will not fit. If that sounds like something you would be interested in doing, just let me know, and I'll post pictures and links to the items on Amazon.

Oh, and the thumbs up worked. It looks like it went to thumbs down for you, because that would be what you would click to remove the thumbs up. It's confusing, and you are far from the first person to be confused by that.

Best of luck to you! Let us know how it comes out!

 

[OutkastBoss]

Those 2 boxes each hold a coil for each engine. There is supposed to be 2. I have a twin 787 Speedster and I have 2 eboxes. Mine are at a different location though but they are there.

Awesome that brings me back to only these questions, I will search around on my own and keep an eye out for responses here. Will definitely post up how it goes either way!

So if 150 psi is ideal and the motors have some age on them, will a slightly lower compression be acceptable as normal engine wear, and if so when is it "too low". Also if compression is low on one or more cylinder does that mean rebuilding the top end or swapping in a rebuilt is in the near future? If so do you happen to know a rough estimate on a top end rebuild or the cost of a rebuilt from a company with a decent reputation and price?

As far as compression testing procedure do you simply pull the plug wires and replace the cylinder you are testings plug with the tester and crank the engine a few times? Is it important to have plugs on all other cylinders of testing motor? Should this check be done on a "cold" motor?

If we let it warm up and shut it down for 15 minutes only to have it not start back up, what is that indicative of? I know on my Jeeps we can get "heat soak" that causes misfires by heating the fuel rail and injectors causing fuel to vaporize. Would it also be indicative of a cooling issue on this craft, carburetor issue or possibly something more serious? (my jeeps are 2000+ so I know very little about carburetors) I did a brief search and saw something about a temp sensor issue but wasn't sure if it was applicable to this model boat/motors.

 

[XP 787]

Compression numbers need to be within 10% of eachother.

A new top end is about 400 bucks. This includes you doing the labor but is not hard to do at all.

When doing the compression test pull both plug wires off sparkplugs and place them on grounding posts. (On the 2 black boxes we were talking about in engine bay) Remove sparkplug and install compression tester. Leave other sparkplug installed. Crank the motor over at least 5 revolutions.

 

[OutkastBoss]

I really like that bow seat insert, I've never seen that on any Challenger I've seen, and I don't have one either.

If you or anyone is interested I could take it to our local boat upholsterer and get an estimate on having some made, apparently they are rare

I purchased a mount and a spare tire on Amazon as well. You need a special mount that slants the spare tire, because a straight one will not fit. If that sounds like something you would be interested in doing, just let me know, and I'll post pictures and links to the items on Amazon.

Please post up the link for the tilted spare mount and rim if you could. I haven't found the same 14" rim mine has but did see this https://www.amazon.com/gp/product/B0...A2AAS4KMPY7DS7

We got the boat! I want to post up a thread with pics, future progress and some trip reports soon. Does this site host the pictures or do I have to link them from a 3rd party? I just lost all of the pics in both my Jeep and off road trailer build threads because of Photobuckets latest shenanigans. So if I need to have them hosted by a 3rd party please recommend a free one.

You guys would probably have a better idea but I feel like we got a pretty good deal on it. He was originally asking 6500 but agreed to 6k before the test ride. I got to do a compression test and check it out in and out of the water. Because of some problems in the test ride we settled on $4700

The boat is in pretty nice looking but has a few scrapes in the hull that go below the outer white color to the (fiberglass?) underneath and the rubber strip down the center underneath is coming unglued a bit up front. It also has a few minor interior trim pieces and upholstery that I would like to fix. It still looks nice for it's age and everything seems to work as it should. It came with a towable cover and he left all of his stuff in there, assorted ropes, 2 anchors, 3 bouys, Oar, tools, extinguisher, flares etc. The trailer bearings have a small amount of play but I think they just need tightened and regreased. It has a newer tongue jack and hand winch that are very nice as well!

As extra excitement we had a tire blow out on the way home and throw a fender off of the trailer (already fixed). The fender scratched one of the decals down the side but that's minor. The side that blew had good tread but looked like an older tire. The other side was newer and in great shape so we got the matching tire to get us back on the road. it was a Goodyear Marathon 205/75r14. We definitely need to find a new rim and add a spare mount.

 

[OutkastBoss]

Now for the more important stuff that worried me;
It had a little oil residue (not much) left inside under the motors and outside on what was maybe the exhaust holes and onto trailer a bit. He said the raid valve or valves had gone bad and he replaced them all so it doesn't leak anymore.

The motors started right up and it smoked a bit until warmed up which he said was normal when it sits for a bit. the motors both revved all the way up the tach smoothly and easily restarted after warming up and being shut down for a few minutes. They sounded good but the boat had no real acceleration or speed. I believe he was legitimately flabbergasted and embarrassed at the boats lack of performance during the test run.

As far as the compression tests I am not sure I did them correctly and want to re-do them. He seemed to be unsure about cranking it too long so I think it cranked over 3 or 4 times followed by a short pause and a second 3 or 4 cranks. hopefully that doesn't change the results compared to a continuous crank like we were instructed to do. All 4 plugs went up to 90 on the first few cranks and then up to their final readings on the second crank. One motor read as 120/120 and the other 120/110 I plan on re-doing it with a fully charged battery, does it need hooked up to a hose to crank it safely?

I like to and usually need to learn to work on my own things but use shops for diagnostics before I research and swap parts. I will probably drop it off at a shop to get it thoroughly checked out. I may even just pay to get it back on the water with the money he knocked off the purchase price.

Do you guys think it could be drivetrain related? The impellers look a bit knicked up on the edges and I don't know how to check the wear rings. I imagine there is a gearbox and driveshaft that I could check for play or metal in the fluid but will have to look closer tomorrow.

 

[Lumps]

I would say not to put the hose on for the compression test. it needs the exhaust gas to keep water out of the engine. 120 seems low. I think 140 ish is normal. the smoking a bit after it sits is common and probably every old engine will have this issue. but it is a sign of the seals weakening on the crank (also the rotary valve?) anyway all 2 strokes smoke. its just the nature of things. as the seals get worse it will smoke more and more. I don't think this is something to worry too much over unless its at the point where the smoke is too much for your tastes (if that's the right way to put it). at least you know you are getting enough oil in the cylinders right?

I would definitely take a look at the impellers and wear rings. if you have to replace them then it would effect your purchase price / total cost of ownership.

there are no gears in these boats (the mercury versions do). the shaft coming out of the engine drives directly one to one to the impeller. there is oil in the stator (where the impeller shaft ends in the jet pump). this should be checked for the quality of the oil (ie milky due to water getting in) and for metal.

 

[OutkastBoss]

I would definitely take a look at the impellers and wear rings. if you have to replace them then it would effect your purchase price / total cost of ownership.

I will do some research on how to check the wear rings, impellers, and how to r&r them this eve

there are no gears in these boats (the mercury versions do). the shaft coming out of the engine drives directly one to one to the impeller. there is oil in the stator (where the impeller shaft ends in the jet pump). this should be checked for the quality of the oil (ie milky due to water getting in) and for metal.

I didn't have much time but I tried to look I didn't see any access panel, dipstick or fill hole to try and check that fluid in the stator. Is it inside that metal box attached to the rear of the motor sitting underneath the black ignition boxes?

Thanks for the help so far and a place to organize my thoughts and reference back SDF!

 

[Lumps]

The fill hole in the stator is in the cone that should be visible out the very back of the pump

 

[OutkastBoss]

Re-did the compression tests with a full battery and got higher numbers!
One was like 137 and 142 (almost 140 on both cylinders).
The other was 150 and 165. (There is paperwork indicating this one was new in 2009)

With the first full 5 seconds of cranking the numbers were a little more consistent from cylinder to cylinder but I did a second few cranks until the gauges went as high as they would to get the final numbers.

I called around a few boat repair places today and they had no interest in looking at or fixing up a seadoo boat. It was closed today but there is a local powersports place that mainly sells quads and also Seadoo Pwcs. When we had a pwc that is where it was worked on so hopefully that is where we can get it looked at.

I kinda tried to find the stator fill plug again (didn't ever have time to do my own research) but I didn't have much time so I didn't get far, it is pretty hard to get down in there and see anything really. Hopefully I will find some more free time to do research on working on these.

 

[2x2smoke]

Seems like there is still confusion of terminology here. There are two "stators"

One is part of the magneto at the front end of the engine , towards the bow of the boat (inside the hull)

The other is part of the jet drive at the back or stern end of the propulsion system. (outside the hull) This is where the bearings an oil bath are located that support the impeller. We are looking for a jet propulsion problem rather than an engine problem, right?

 

[OutkastBoss]

Seems like there is still confusion of terminology here. There are two "stators"

One is part of the magneto at the front end of the engine , towards the bow of the boat (inside the hull)

The other is part of the jet drive at the back or stern end of the propulsion system. (outside the hull) This is where the bearings an oil bath are located that support the impeller. We are looking for a jet propulsion problem rather than an engine problem, right?

Yes we are looking at a propulsion problem and that does help me get more on track with what and where I need to look, thanks! I watched a few videos on youtube of jet pump rebuilds, that clarified a LOT. It doesn't look that hard with the right tools but I don't have a press.

The hunt for a local shop to check it out hasn't gone well, I live in Saint Louis Mo so it's not a small town or anything. The closest shop I can find so far that would look at it is 3hrs away at the Lake of the Ozarks.