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  Topic Review (Newest First)
04-28-2015 01:18 PM
Re: Perkins 4.108M DIY Rebuild -- A Narrative

Originally Posted by eherlihy View Post

Now that PorFin is back, I want to know how it turns out - before he gets distracted again...
Patience, my friend, patience.

Let's see...

- House in VA renovated and sold? Yep -- just closed a couple of weeks ago.
- Off crutches and starting to walk again? Yep, albeit with a very aggravating limp.
- New abode in FL selected and purchased? Not yet. As one might guess, the wife's got this pretty much at the top of "our" (which translates into "my") priority list.
- Quick commute to work on the boat? Not so much -- it's about 12 hrs door-to-boarding ladder.
04-28-2015 12:29 PM
Re: Perkins 4.108M DIY Rebuild -- A Narrative


Now that PorFin is back, I want to know how it turns out - before he gets distracted again...
01-30-2015 08:50 AM
Re: Perkins 4.108M DIY Rebuild -- A Narrative

Dude, you realize that you started this epic in December of 2012... Twenty five months ago...

We want pictures!!! (motor-porn).

I'm glad you're back!
01-30-2015 12:07 AM
Re: Perkins 4.108M DIY Rebuild -- A Narrative

But we still appreciate it Anyone who takes the time to share with others gets a big thank you from me for what it's worth, thanks Porfin!
01-29-2015 11:07 PM
Re: Perkins 4.108M DIY Rebuild -- A Narrative
01-29-2015 11:01 PM
Re: Perkins 4.108M DIY Rebuild -- A Narrative

OK, just to set the record straight...

I completed the rebuild, and the engine runs like a champ. Smooth, good pressure, clear exhaust. Shortly after I had it running (in my driveway) and...

I had to drop the project, and prepped the motor for storage.

And there she sits, waiting for a blissful reunion with the boat.

Volume 2 of this epic saga will address the reinstallation.

I'm betting nobody here is gonna pay me an advance on THAT tale...
08-27-2014 05:08 PM
Re: Perkins 4.108M DIY Rebuild -- A Narrative

Within this thread there is a reference to the Perkins Build List #ED70058, and I'm wondering if anyone came up with an electronic copy that can be shared. I also have been seeking a copy of the document for similar purposes as described in this thread, and cannot locate anyone with a copy.

Any assist would be appreciated
06-28-2014 10:25 AM
Re: Perkins 4.108M DIY Rebuild -- A Narrative

Edit: Couldn't you have simply put the pin of your dial indicator down the injector hole to measure TDC? It would have saved pulling your valve spring etc.[/QUOTE]

That's exactly what I did when I timed mine. PorFin is correct that you cannot get an absolutely clear shot to the piston crown by going down through the opening in the combustion chamber insert. But on my engine at least it was only a few (maybe five) degrees away from "parallel". I visualized the situation as a right triangle made from a perfect parallel, the amount of error between the perfect and the actual, and my piano wire which represents the actual. The piano wire is the hypotenuse of the triangle and at the amount of error that I saw is very nearly the same length as the perfect.

Is that clear as mud?

Anyway, I removed the rocker cover in order to identify #1 cylinder's compression stroke TDC (both rocker arms "loose"), which allowed me to get close to TDC. I then cut a length of 0.072 piano wire (available at a hobby shop) to a length sufficient to touch the piston crown and extend far enough out of the cylinder to reach my dial indicator. I removed the threaded end of the dial indicator so that the wire would fit up inside and couldn't slip. I mounted a magnetic base on top of the (now bolted down) rocker cover and set the dial indicator's height about midway through its travel. Then I rocked the crankshaft back and forth to find absolute TDC and zeroed the dial indicator.

Then I rotated the engine OPPOSITE to its normal rotation until the dial indicator read 0.200 inch. THEN I rotated the crankshaft in its normal direction until it read 0.120 inch (the static check point for the 4.107 per the workshop manual fuel injection pump table).

I removed the inspection cover from the (installed) pump and rotated it until the "A" mark lined up with the circlip as PorFin's beautiful pictures show (how do you take those anyway?!)

Tightened everything up and I was good to go!

Now to finish the installation in the boat...

Oh, although I used the ones that I already had, if you're interested in doing this yourself you don't need a hugely expensive dial indicator and magnetic base. Harbor Freight has them for less than $30 US TOTAL for both items.

Ray Russell
Valiant 40V163
03-24-2014 11:06 AM
Re: Perkins 4.108M DIY Rebuild -- A Narrative

Originally Posted by JSROOKS View Post
Wow, what a great project. My 4.108 has a slow main bearing leak, so I will be in partial rebuild mode soon I think.

Does anyone know the maker of the great-looking alternator tension fitting that Porfin has used here? I have never see one like this before.

But then again, I don't get out much.


Mcmaster Carr:
9 59915K273 1 Each Ptfe-lined Stainless Steel Ball Joint Rod End, 5/16"-24 Rh Male Shank, 5/16"ball Id, 1-1/4"l Thrd
10 59915K232 1 Each Ptfe-lined Stainless Steel Ball Joint Rod End, 5/16"-24 Lh Male Shank, 5/16"ball Id, 1-1/4"l Thrd
11 8419K12 1 Each Easy-adjust Threaded Connecting Rod, 2" Overall Length, 5/16"-24 Threaded Female Ends

I did the same modification to my 4-108, but took it down to the starboard engine mount flange so as not to have to shorten the tie rods. let me know if you need more info.

03-14-2014 07:07 PM
Re: Perkins 4.108M DIY Rebuild -- A Narrative

my 4-108 is ka lunk and has its own thread..... and is touring mexico as we speak, as parts are in casimiro castillo, manzanillo, and better than i do at this point....will have completely brand new gutz. saved were the cam and crank, and block and head is machines,and the rest is new. thank gods is pesos.
after this i have to go get my jib repaired better, as the repair done was FAIL. and a tank..mebbe i can sail again next year....
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