Hi everyone,

 

I'm restoring my engine which is completely disassembled right now (1.3 MH 55hp carb). New parts should arrive in few weeks but I'm thinking in advance on how I'm gonna fit all these stuff together.

 

My camshaft is already uninstalled and separated from the head. Whats is the best or easy way to install the seal when I'm gonna assemble the head ?

- The usual way : With camshaft installed then push the seal in its place

- Or another way : Without camshaft installed, put the seal in the camshaft outside of the head then install the camshaft and thight the caps

 

Below is a pict from partsouq (link at the end). The seal is part "2" in picture and I've added and arrow where I may put the seal without the camshaft installed then lock the bracket etc... (let me know if I'm not clear. Not sure "bracket" is the right word to use there). Obviously, placing the seal before the camshaft is probably easier than pushing it when working with the head and block installed in the engine bay. But not sure if that way may crush or damage the seal

 

Link (Partsouq) : Cylinder Head

Edited 19 November, 20214 yr by cedreex

i would fit the lubed seal into place before tightening the bearing caps , as you tighten double check its seated nicely 

Edited 19 November, 20214 yr by steveo3002

Not much difference. I prefer fitting seal with camshaft out the way. 

You can oil it and bash it in straight with a flat piece of wood.

Guiding the clean oiled camshaft in through dizzy end hole and other holes is quite easy.

 

Is that a pic of a hydro head, because I thought MH to January 1989 was still mechy?

 

If it is hydro (2G)  you have to tighten cam bearing caps 2 and 4 then 3 then 1 and 5

(numbered from left to right where your arrow points).

 

Edited 19 November, 20214 yr by dvderlm

No MH was hydro introduced in 1985 and 2G revised it.

Ignore me.

Thank you all for your answers. Good to know that there is no risk to damage the seal by tightening the bearing caps instead of pushing it in the hole with the camshaft already tighten. Installing the seal would indeed consist of bashing/pushing the seal straight with a flat piece of wood. But having the block mounted, there's quite small space between the car body and the head. Anyway, I'll think about these 2 solutions vs assembling the whole head and put it in place (not always easy to align this 15kgs bare metal and the head gasket).

 

My engine have hydraulic tappets (so yes it's an hydro head). I believe 2G engines are very rare in France because maybe they were not supposed to be distributed by VW in France (Polo 2F Genesis maybe ? but probably imported). I was not aware of the thightening order for the bearing caps on hydro heads. I will note it to make sure I won't forget it. I was only aware that I should wait about 30 minutes after installing the new full oiled hydro tappets before running the engine. This will allow time for the tappets to adjust their gaps before running the engine for the 1st time after assembling.

 

One last thing I wanted to mention is that I have 2 polo, one is a mk2 and the other is an mk2f. Both have an MH carb engine, the mk2 head have 2 springs per valve and the mk2f have 1 sping per valve. I'm planning on using the mk2f head because it is in better condition that the other (I will check if this is still true after cleaning them). I know there won't be any advantages in using the double springs on the single spring head but I would like to use the double ones. I don't know if the valve seat of these 2 heads were made of the same (i.e have the same metal, same solidity, etc...). This will be my 1st time engine assembling from scratch (bottom from head) 🤞

Edited 19 November, 20214 yr by cedreex

My mk2 is a March 1991 (one of the lastest production ?)

heads should be the same 

 

only differences avail were the double valve springs and some had 7 or 8mm valve stems ..not sure when they changed , 7mm may give optimal gas flow if you have the choice

 

do not mix up the cam shaft caps between heads , they must remain in the original place 

To align the head to gasket and block I cut the ends of 2 of the old cylinder head bolts. Cut a slot in the top. Screw them in back left and right loosely.

 

Lower the block over the the two headless bolts.

Fit  2 new bolts at the front loosely. Unscrew the headless bolts with a screwdriver and fingers.  

yep same here....works a treat 

 

dont forget to clean the bolt holes properly ...oil or coolant will effect the torque

Thanks for tip on using bolts to ease head and gasket alignment. This will help very much indeed.

Both engines have 8mm valve stems and I won't swap or mix the parts between those heads. Excepted the double springs instead of the single spring because I would like to keep the mk2 like it used to be (i.e double spring valve with new valve cotter of course). If the valve seats of both heads were meant to support single and double springs then that's fine for me.

Edited 20 November, 20214 yr by cedreex

I suppose I should not mix or swap parts between the bottom ends also (e.g crankshaft/pistons) ?

well the crank and pistons will be worn to the original engines , so isnt the best idea 

 

why do you need to swap crank and pistons over....i would choose the lowest mileage /nicest engine and fit that complete

5 minutes ago, steveo3002 said:

well the crank and pistons will be worn to the original engines , so isnt the best idea 

 

why do you need to swap crank and pistons over....i would choose the lowest mileage /nicest engine and fit that complete

 

Yes I would probably choose to use the lowest mileage bottom head which is my mk2f's. Since I'm certainly going to use the mk2f's head, that means I'm gonna use the whole mk2f's engine. Excepted the water pump and crankshaft/camshaft pulley which are gonna be those of the mk2 to keep thing as original as possible. Even though I'm not gonna sell this car as I certainly gonna work very hard to get it finished and running.

 

I was asking this question about swaping parts of the bottom end because even though choosing the lowest mileage bottom end if the way to go, I must make measures and check the dimensions of the bottom ends. I mean check the crankshaft/segments clearance or undersizes, cylinder bores, etc... I don't know if what I saying is clear enough about what I mean by taking measures/dimensions. Anyway I hope the lowest milieage should result in good measure results that the mk2's. I don't have very high quality tools for these checks but I'll try to get as precise measurement as I can.

i would go as far as inspect the sump pan for sludge and the clyinder walls for honing cross hatch pattern 

 

if you take the crank bearings out to measure you may as well ft new ones , and while theyre out then the pistons can come out to check the rings arent gummed up

 

it can turn expensive quickly  

1 minute ago, steveo3002 said:

i would go as far as inspect the sump pan for sludge and the clyinder walls for honing cross hatch pattern 

 

if you take the crank bearings out to measure you may as well ft new ones , and while theyre out then the pistons can come out to check the rings arent gummed up

 

it can turn expensive quickly  

 

I have already ordered the bottom parts (4x set of 3 piston rings, 10x crankshaft bolts, 10x crankshaft bearings, 4x crankshaft washers, 8x piston rod bearings). The total cost was a little more than 117 euros. I didn't received those part yet though. It's expensive indeed but I have think about it several days on should I or shouldn't I renew these parts and since I was disassembling the whole engine appart, I've finally decided I would go on renewing these parts. I hope I didn't make a 117 euros mistake... 🤞

 

I've bought a micrometer and some precision tools to check the clearances and undersizes of the bottom engine. This is a 1st for me and my tools are not some high grade manufacturer so I hope I'll have some descent accuracy.

I'm going to keep my mk2 so even though my budget is somewhat limited, I've made these expenses but I'm not sure I'll spend the same or buy the same bottom end parts when I'll restore my mk2f after I'm done with the mk2

so hone the bores before fitting the new rings and read up on correct break in procedure

 

i spent alot on my abd on a home "rebuild "  hone,rings,bearings ,bolts  ,oil pump chain etc ,its done 5k miles now and uses more oil than the old mh ...honestly vw knew what they were doing , i wouldnt build another one as it was a waste of money ..guessing i didnt break it in well but eeveryone has different ideas on break in 

Wow...I'm a little afraid of what you just said... I want to rebuild the engine right and I know I can make mistakes. But I must believe I can do it right. Otherwise I won't have the right positive mental to achieve it 🤞

 

What do you mean by "break in procedure" ?

Sorry I get it. I've understand what "break in procedure" means

yeah i did mine all as it should be by the books ...hopefully yours will be better

 

have both engines done high km?

From what I understand from searching for resources. The break in procedure would consist on about 1000 kms divided on several phases. The 1st one consists of running between idle and a max of 2500 rpm. I've not already dive deep in the break in phases but I'll make sure I'll understand it well.

 

I didn't find mention about "hone the bores begore new rings" though. What does it consists of ?

hone = grind on a new cross hatch pattern , the piston ring seller should say what grade it needs to be ..i think maybe mine was 240 or 180 

1 minute ago, steveo3002 said:

yeah i did mine all as it should be by the books ...hopefully yours will be better

 

have both engines done high km?

 

The mk2 engine have about 172 000 kms and the mk2f has 112 000 kms (sorry I used to metric not imperial). Though mileage may not reflect the engine state. From what I've seen until now, the mk2f head is in better condition that the mk2's. Especially the mk2f head has good condition valve seat while the mk2 has a bent exhaust valve on the 3rd cylinder (1st cylinder on the belt side, 4th cylinder on the dizzy side)

break in procesdures vary depending on who you talk to

 

most say no idling ...get in and drive 

 

some say baby it with low revs , others say drive hard and use lots of revs and overrun 

 

non synthetic oil and change it often  

1 minute ago, steveo3002 said:

hone = grind on a new cross hatch pattern , the piston ring seller should say what grade it needs to be ..i think maybe mine was 240 or 180 

 

I'm afraid I don't have the right tools to achieve this on the cylinders. I believe I have to hone using a perfect vertical tool which I don't have. I want to know if this is very mandatory depending on the cylinder state