470. Alpha one water intake, kinked!!!

[dieselram94]

Ok, pulled the drive off this 1987 Larson alpha one with a 470 mercruiser. I changed bad gimbal bearing and seal. I believe the water in the bellows lead to it going bad...lol! I just purchased this and was told it sat tied up to the dock two years ago, pulled out last summer and previous owner heard the bad gimbal bearing and just didn't use it as a result. So it's been two years since being used. Three years ago a head gasket was installed. After inspecting bellows for cracks I discovered the water hose is mostly kinked off and deteriorated at the kink with the belting showing. I know these motors are sensitive to getting hot so naturally I'm a little nervous of the head gasket. Oil is clean with no coolant in it. Antifreeze is down some but I attribute that to the very slow drip from water pump seal at the cam.
I'm going to obviously change the bellows and water hose but am now wondering if I end up doing gasket how often do these 470 blocks warp? Or pull threads from head bolts? I really don't think I have a head gasket problem but I just get ocd about things! Lol

 

[dieselram94]

No Title

Not sure if completely kinked off...

 

[Newbie@boats]

That hose is kinked enough to be replaced regardless of what motor is in the boat. It looks like it may have been replaced at one time and someone used to long of a piece. I just replaced the bellows on my boat and that intake hose I got the right diameter and the right length according to merc specs and it came out good

 

[dieselram94]

Yeah, definitely going to replace it. I'm hoping I can find it and bellows locally tomorrow. I'm just really hoping head gasket is ok. I'll check compression tomorrow.

 

[stonyloam]

It can be very difficult to get that hose on with the transom side fitting in place. You might try unbolting it, fitting it into the hose, and rebolting it in place, that way you can make sure there is no kink.

 

[dieselram94]

Ok, ordered all new bellows plus an exhaust tube. I cut the kink out to verify hose size and its 3/4"
I will get a hose barb so I can hook my hose on to the cut off hose and run the motor tomorrow and install into out drive the new water pump. I also am going to make the plyers into crimping tool for the shift cable bellows unless someone knows where I can buy the proper tool? I did a Google search and came up with nothing. I did hit the key and it fired instantly so I just shut it off. I really think the head gasket is fine

 

[stonyloam]

You can use a cable tie for the shift cable bellows (small end) just snug it up good and tight and clip it off.

 

[dieselram94]

Ok, checked compression and cylinders 1,2, and four are all about 135...I didn't check #3 as space was tight for my socket. I started it and it ran great and never got above 150* measured with infrared temp gun. Gauge showed less than 120 the half hour I ran it. I think this boat got luck to have someone else working on it! Even the weep hole dried up. Bellows will be here by the weekend, then it's off to the lake to try her out!

 

[dieselram94]

Ok, bellows are off. Hopefully start reassembling tomorrow. Anyone know the correct length for the 3/4" inlet hose? I've seen multiple lengths stated as "correct"

 

[Newbie@boats]

I looked mine up in the Sierra catalog...don't remember exactly, but couldn't you just measure the hose you took off?

 

[dieselram94]

Old one was kinked so I think it was wrong length. I also cut it to aid removal. Seems length is often confused. Somebody must know what the factory recommends?

 

[Newbie@boats]

I just looked it up in my Sierra catalog and it looks like both 18-3601/18-3602 are the same hoses 3/4x13 7/8 long

I looked it up for alpha 1 gen 1/gen2

 

[dieselram94]

Thanks!!!!
Your a life saver!!