Head removal of Perkins 4.108

[pr2501]

If I did understand them , they intend to put some material which should be better that what I have now.

Plate steel is it a "simple" steel?

[pr2501]

My spare parts have been shipped today from Newport News, VA, United States.
I have at least five days or maybe even 10 days before I will have them on the boat.
So I can easy make a plan to be prepared to work for assembly.

First phase
1. Grind down old paint from block
2. Inspect oil lines
3. I need a puller to take liners out and also to install new with it.
(when I will go in shop to make me a injector
flange I will also ask to make me a puller and ask to inspect rods if they are not
bent)
4. Install the crank shaft with main bearings
5. Check the clearance with plastic gadgets
6. Install the end plate trust washers and check the clearance
7. Install the pistons on the rods
8. Install rings on pistons
9. Insert pistons
10. Install rods bearings
11. Check the clearance with plastic gadgets



Is there something that I have also take care of? Or is it that should I proceed differently?

Is it there a special reason to take cover tappet inspection down?

[rbk]

Check the tapets for sure. Cylinder liners can be removed carefully with a flat head screw diver and a mallet similar to removing a cutlass bearing. Cut lengthwise and collapse inward, but do not damage, nick or scratch the block as it can warp the new liner. To reassemble you can make a simple press with threaded rod, plate steel/washers and nuts. Also make sure you don’t over press, better to measure and slid in a little further and have to try and back it out.

[jimbunyard]

Originally Posted by pr2501

My spare parts have been shipped today from Newport News, VA, United States.
I have at least five days or maybe even 10 days before I will have them on the boat.
So I can easy make a plan to be prepared to work for assembly.

First phase
1. Grind down old paint from block
2. Inspect oil lines
3. I need a puller to take liners out and also to install new with it.
(when I will go in shop to make me a injector
flange I will also ask to make me a puller and ask to inspect rods if they are not
bent)
4. Install the crank shaft with main bearings
5. Check the clearance with plastic gadgets
6. Install the end plate trust washers and check the clearance
7. Install the pistons on the rods
8. Install rings on pistons
9. Insert pistons
10. Install rods bearings
11. Check the clearance with plastic gadgets



Is there something that I have also take care of? Or is it that should I proceed differently?

Is it there a special reason to take cover tappet inspection down?

Caution is needed.

Here's a page from a Spanish language service manual regarding fitting new pistons. Unless something has changed, they must be fitted individually to their respective cylinders.

Here is a link to the manual de taller.

https://www.slideshare.net/blancaisa...-4108-38659707

Since you've ordered the parts I assume you know for sure if you have a 4108 or a 4107. If you have a 4108, the liners must be removed and installed by the machine shop as they are an interference fit and have to be pressed in. The protrusion of the liner above the block surface is specified and it is important that it meets this specification.

if you have the 4107, you have wet liners, which can be removed and refitted by hand, but the pistons still need to be fitted to spec.


Also included are a couple pages in English, because I'm not absolutely sure what the Spanish page says...

[pr2501]

What is holding liners not to move on 4.108 once he is in its place?

I am not sure if I can set protrusion of liners to be 0.686 mm above the block.
I will have to pay 80$ to install liners in the shop.
The biggest problem here is the transport. And I was hoping from the beginning to do all on the boat by myself.

[jimbunyard]

Originally Posted by pr2501

What is holding liners not to move on 4.108 once he is in its place?

I am not sure if I can set protrusion of liners to be 0.686 mm above the block.
I will have to pay 80$ to install liners in the shop.
The biggest problem here is the transport. And I was hoping from the beginning to do all on the boat by myself.

Dry liners are an 'interference fit' in the block, which means they are held in place by friction between the liner and the block caused by the difference in the OD of the liner and the ID of the hole in the block that they fit into, in other words, the liner is a tiny bit larger than the hole it is pressed into.

Yu can probably borrow or make a manual press to remove and install the liners, but unless you can't get the block out of the boat, it will probably be more economical, in terms of both time and money, to bite the bullet and make the effort to bring it to the machine shop. Again, unless something has changed, the piston heights have to be fitted to their individual cylinders, and this must be done at the machine shop with the crank assembled in the block. Unless of course, the pistons turn out to be the correct height from the factory.

If it turns out that you have to install the liners yourself, getting them to the correct height in the block is not much of a problem if you use the method illustrated in the image below. I hope it's self explanatory, if not let me know.

[pr2501]

Workshop manual says that the liner inner dimension is 79.40
I was thinking to make mandrel to be 79.38.
But what should be the other dimension of mandrel?

What exactly they do with the pistons in the shop?

[pr2501]

If I go

Cut lengthwise and collapse inward

by rbk instructions I will then don't need the mandrel.

[jimbunyard]

Originally Posted by pr2501

Workshop manual says that the liner inner dimension is 79.40
I was thinking to make mandrel to be 79.38.
But what should be the other dimension of mandrel?

What exactly they do with the pistons in the shop?

The parent bore (the size of the hole in the block) for the liners is 82.525 to 82.550 mm so I would think 81.5 to 82 mm would be about right for the OD of the removal mandrel.

The pistons are supplied with extra material on their faces so they can be machined to the proper height above the top face of the cylinder block (not the top of the liner), .051 - .152 mm.

What has to be done is the rotating assembly (crank and bearings, rods, bearings and pistons (without rings) has to be put together, and then each piston height has to be measured at top dead center for that cylinder and then machined to ensure that it falls within the .051 - .152 mm spec higher than the upper surface of the block face, with the goal being to get them as close to each other as possible. The point of doing this is to ensure that each cylinder displaces the same volume and thus delivers the same amount of power, which results in a smoother-running engine that has a longer life.

It should be possible to carefully measure each piston height uncut, calculate the amount to remove for each, disassemble the parts, bring them to the machine shop to be cut, and then reassemble and check, but I still have doubts that this will be the most efficient route to take...

Of course, I really don't know your situation logistically...

[jimbunyard]

Originally Posted by pr2501

If I go by rbk instructions I will then don't need the mandrel.

That should be considered a method of last resort, and will likely be much more difficult than you imagine.

Additionally if you damage the block while doing it, even if you can clean the damage up afterwards, as the combustion heat is transferred through the liner into the cast iron in the block, uneven contact between the steel of the liner and iron of the block can lead to localized hotspots, with unknown consequences...

I would consider this option as 'attempt at your own risk'...

[pr2501]

I have measured my existing pistons.
And got to conclusion that they are all the same.

43.63 ± 0.02 from the inner hole gudgeon pin to the top of the piston.

I have find out (I have find the bill for the work) the my engine was rebuilt in 2002. They did put pistons (31351454 Perkins KZF P) in it without any work on them.

I will risk and do the same. But I will install pistons on rods without piston rings and measure the clearance. In case I will be out of .051 - .152 mm I will then return.

As I will use mandrel to pull out old liners and to insert new one. Maybe it will be no need for the shop. Because I did also got an old injector from the another marina mechanic where I went yesterday and bought flange from it for 40$. Still I will have to check this injector before I might say that I have one injector for spare parts.
And about checking of rods if are they bent. I will trust my naked eye which says that they are straight.


The dimension marked with "?" in before attached mandrel image will
be 81. 8

[pr2501]

I am staying in one marina which is on Atlantic coast of Panama and the shop is on the Pacific side. I can not rent the car because my international driving licence is expired and I have left original at home.

Maybe I could find someone which will be willing to help me and I will bring all in shop.

[pr2501]

What is the way to inspect lubrication oil lines?

[rbk]

If they are worn or seized at the fittings it might be time to replace them. I just had mine done up by a local pump place that does hydraulic lines.

[pr2501]

And when they made me the mandrel for liners extraction, I tested it with new liner (which I got from the Panamanian customs yesterday) and i did find out that mandrel does not fit in the liner.
It is because liner inner dimension is not 79.4 but it is 78,7.

So then there is no other way I will have to go to the shop because of liners installation.
It is that liner does not come finalized, they have to be grinded.
Correct?