Is this rebuilable ?

[johnfergusson]

Hi,<br /><br />I pulled the had to look for a water leak as it has been weeping arround the head.<br /><br />It is or at least was a 1978 140 #140843C<br /><br />As best I can tell it's been rebuilt at least once probably for the same reason as this time.<br /><br />I guess it has broken a ring and the fragments have bounced arround a few times. I think bits may well still be embeded in the piston.<br /><br />This was still running, down a bit on power though. It has not run though for better than 2 years. This little suprise has been lying in wait for quite a while.<br /><br />This is the number 4 piston. Number 1 shows sign of having being rebuilt once all ready from doing a similar trick.<br /><br />I have a couple of questions.<br /><br />1 Is the non powerhead portion of the motor spare parts now?<br /><br />2 What did this? Carbon buildup? or did I not get the carb quite as clean as it should be.<br /><br />It was running with 24 deg btdc allowed up to 28...<br /><br />The starbord bores are 3.5030 and 3.5020 respectivly the port side both appear to be 3.500 but I did not have the right tool to confirm this. There apears to be some scraping of the bore and I am unsure if this can be honed out.<br /><br />Does the 030 on the pistons mean they are 30 thou over allready? or is it just a part number.<br /><br />The port head is most likely history, the starboard head shows signs of having suffered a similar problem in the past though no where as badly.<br /><br />There was also excesive clearance on number 3 piston as well and no baffles in the starboard bank<br /><br />Thanks in advance for your advice.<br /><br />The piston

<br /><br />The Head is not prety either...<br /><br />

<br /><br />And the bore is least frightening of all.<br /><br />

 

[mikeyzx2]

Re: Is this rebuilable ?

Well.....welcome to iboats! I was like WOW that piston is tore up! When you are talking about baffles, are you describing the little rubber deflectors placed in the block to route water flow? Safe to say, you have at least two things to replace, at the least. This one's best left to the experts....

 

[Dhadley]

Re: Is this rebuilable ?

Judging by the coking build up and the history we'd bet that when it ran good the top rpm was in the low 5000 range. It simply looks like typical coking damage. <br /><br />I'd bet its still rebuildable. Once you get it apart and have it measured we'll know for sure.

 

[johnfergusson]

Re: Is this rebuilable ?

Dhadley you are correct it was difficult to get it to pull much over 5400rpm. 5500-5600 was the best I ever saw. <br /><br />A can of power tune would most likely have saved this. It has been laid up for a while as we are working on getting the hull back to it's correct weight. Some of the dark liguid is engine oil that was pumped in to keep things nice an oily while it sat.<br /><br />The hull was carying a lot more water than strictly necesary. Something about driling holes in the stern and no silicone got the foam all nice and wet.<br /><br />The rebuildable is more likely to come to economics. How close were these old 140's to the stated power as I had heard that 105 was closer to the truth.<br /><br />Well at least I did not kill it by getting the carbs wrong.

 

[Dhadley]

Re: Is this rebuilable ?

Actual propshaft hp is 110-112-115. Those are great motors but dont have anywhere near the torque of a V4 looper.

 

[johnfergusson]

Re: Is this rebuilable ?

How big can the chips removed from the edges of the ports be before it's scrap metal? There is some damage to the intake and exahust ports. There are 1/16" chips taken out of a couple of the intake ports and these are deeper than a few thou. You can get your finger nail into them. It looks like it did a number on the rings.

 

[Dhadley]

Re: Is this rebuilable ?

Actually the rings did a number of the cylinder. Anyway, where are the chips in relation to the ports?

 

[johnfergusson]

Re: Is this rebuilable ?

The chips are removed from the upper edge of the ports, More to the center of the ports rather than the edges. The undamaged edges of the ports are still sharp.<br /><br />Intake middle of the lower 2 ports<br />Exhaust about 1/3 in from the lower edge on the lower port. Intake has fared worse then the exhaust. <br /><br />You can see the exhaust port damage in the pics. The intake damage is bigger.<br /><br />The scoring in the bore is not noticable with your finger nail.