Mivec Owners Group

It is currently 24 Sep 2018 18:23

All times are UTC + 12 hours [ DST ]




Post new topic Reply to topic  [ 25 posts ]  Go to page 1, 2  Next
Author Message
PostPosted: 17 Jun 2004 15:38 
Offline
Administrator
User avatar

Joined: 09 Dec 2003 10:18
Posts: 4439
Location: Hamilton
Country: New Zealand
The disassembled mivec rockers and shafts.
Image

As assembled and how it would be seen looking down on the engine
Image

How does it work?
Oil pressure within the shaft pushes the sping loaded plunger upwards, locking the high lift cam follower to the low lift one.

Potential for fault:
If the plunger becomes contaminated or sticky due to glazing of oil deposits, the plunger won't be able to move and lock the rocker (or may get stuck in high lift mode)
The return spring could fail and leave the plunger in the high lift position.

The oil feeds to the rollers are very fine. There is potential for these to become blocked and so starve the rollers of oil resulting in rapid wear/breakage.

The Tappet adjustment part of the rockers have been known to crack and break.

To Test: (can be done with all parts fitted to engine)
Using a mitsubishi special tool (I've got one) you can pull the plunger up while carefully moving the high lift rocker to ensure overall smoothness and that the plunger moves freely and locks the rocker in place. If the plunger is hard to move, the system will need to dismantled for repair.

_________________
93 Cyborg R (race car)

Waikato@Heart - supporting heart kids through life
Bart Dinger Electronics


Top
 Profile  
 
 Post subject:
PostPosted: 17 Jun 2004 15:53 
Offline
Moderator
User avatar

Joined: 09 Jun 2004 16:33
Posts: 4460
Location: Auckland
Country: NZ
Nice :D

Part numbers for the Gen1(taken for CA4A) are:

MD198555 for the inlet (complete)
MD198556 for the exhaust (complete)

Spare parts (left to right in picture)
MD193525 Guide
MD210682 Washer
MD209134 Ajusting Screw
MD206828 Nut (under screw in picture)


Top
 Profile  
 
 Post subject:
PostPosted: 17 Jun 2004 23:38 
Very interesting. Good job-but where'd you get the tool from? And have you opened up your shop yet, Bartman?


Top
  
 
 Post subject:
PostPosted: 18 Jun 2004 08:43 
Offline
Administrator
User avatar

Joined: 09 Dec 2003 10:18
Posts: 4439
Location: Hamilton
Country: New Zealand
No I'm spending all my time working on my own car :lol: to prove the MPCs abilities. PM me with your requirements or parts dreams. Hard to know what people will want so the more feedback I get the better.

I fabricated the special tool myself. Can make them to order if you want one.

_________________
93 Cyborg R (race car)

Waikato@Heart - supporting heart kids through life
Bart Dinger Electronics


Top
 Profile  
 
 Post subject:
PostPosted: 18 Jun 2004 17:21 
Offline
Moderator

Joined: 06 Jan 2004 17:01
Posts: 1171
Bart, what causes the wear on the square object poking ( for want of a better word ) out the back of the high lift rocker. The other part of the mechanism?.

Also reminds me that i have relatively detailed pics of a cam belt change and some from a clutch change for a 4g92. Must organise them onto the interweb. :)


Top
 Profile  
 
 Post subject:
PostPosted: 19 Jun 2004 09:27 
Offline
Administrator
User avatar

Joined: 09 Dec 2003 10:18
Posts: 4439
Location: Hamilton
Country: New Zealand
Yep well spoted. Photos of that are still to come but its basically just a dampened spring so that when the mivec disengages the rocker doesn't just rattle around on its own. Will clean one up and add it to the pictures next week.

_________________
93 Cyborg R (race car)

Waikato@Heart - supporting heart kids through life
Bart Dinger Electronics


Top
 Profile  
 
 Post subject:
PostPosted: 20 Jun 2004 14:45 
So, do these parts vary just between gen's of the Mivec's or from engine to engine based on car? I'm asking because I'm wondering if the Mivec on the 4 cyls would be different to the 2l FTO engine and the 3l Diamante engine.

And, as embarassing as it sounds, I'm having a hard time visualising how it works with the cams and tappets. Can someone spoon-feed me?


Top
  
 
 Post subject:
PostPosted: 20 Jun 2004 18:25 
Offline
Administrator
User avatar

Joined: 09 Dec 2003 10:18
Posts: 4439
Location: Hamilton
Country: New Zealand
I'll take more photos of it as it gets assembled and explain how it works as I go. Its fairly obvious when you see it all together.

Basically tho, the cams run on those 'rollers' and which move the arms. The valves are worked on directly by the 'tappets'. This is all exactly the same as conventional engine. The only unique bit is that plunger that locks the two arms together.

I've not seen the valve system on the V6 engines in parts, but would assume it works exactly the same way.

_________________
93 Cyborg R (race car)

Waikato@Heart - supporting heart kids through life
Bart Dinger Electronics


Top
 Profile  
 
 Post subject:
PostPosted: 21 Jun 2004 18:26 
Cheers, fella. Looking forward to future bits. I'm sure it will be apparent once more bits are there. I understand how stuff works, just not the exact mechanical picture. I'm learning though.


Top
  
 
 Post subject:
PostPosted: 29 Jun 2004 09:17 
Offline
Administrator
User avatar

Joined: 09 Dec 2003 10:18
Posts: 4439
Location: Hamilton
Country: New Zealand
Image

Here is picture of it all back together.

_________________
93 Cyborg R (race car)

Waikato@Heart - supporting heart kids through life
Bart Dinger Electronics


Top
 Profile  
 
 Post subject:
PostPosted: 30 Jun 2004 14:35 
Offline
Moderator

Joined: 06 Jan 2004 17:01
Posts: 1171
arrghhhhhh my eyes, you need some dirt and grim and filth on that head so its not so shiny. :lol:

You have a chemical clean?.

As an aside, bartman Im trying to take the bottom part of the engine off to replace the gasket. Not the black sump but the next alloy section up.

I have got underneathe and undone all the bolts around the edges but to no avail. I thought it might be stuck a bit but it would not release and i didnt want to force it. I was wondering if you would know if there is a secret "hidden" bolt or something, because as far as i could see i got all of them but it just would not come off?.

any ideas. I have since put all the bolts back in but i think that gasket is leaking so want to replace it.


Top
 Profile  
 
 Post subject:
PostPosted: 30 Jun 2004 17:32 
Offline
Administrator
User avatar

Joined: 09 Dec 2003 10:18
Posts: 4439
Location: Hamilton
Country: New Zealand
I used my secret part washer, hint: its in the kitchen and its made by F&P. The rockers where just cleaned with solvent.

For removing the sump what you need is yet another :roll: mitsubishi special tool. This one is easily replicated. Once you've undone all the bolts, slip a heavy duty paint scraper in there (you might need to hammer it in! be careful!) then just tap the scraper all the way around the sump to break the seal. The glue/sealant they use is really strong.

I don't 'think' there is a gasket in there at all, its a formed in place jobbie so it has to be spotlessly clean/degreased before you glue it back together.

_________________
93 Cyborg R (race car)

Waikato@Heart - supporting heart kids through life
Bart Dinger Electronics


Top
 Profile  
 
 Post subject:
PostPosted: 15 Aug 2004 19:12 
Offline
Moderator
User avatar

Joined: 09 Jun 2004 16:33
Posts: 4460
Location: Auckland
Country: NZ
Here are some more from my Ohlsen Developments visit.

Cylinder head with valves installed
Image

Camshaft holder (LancerMR's)
Image

Camshalft holder installed onto Cylinder head
Image

_________________
MIVEC Data | Mitsi's > 96 GSR (stolen) | 97 Evo 4 (sold) | 96 Cyborg-RX (crashed) | 93 Cyborg-R (sold) | 3x Mirage 4WD (sold) | 98 MIVEC Race car (sold)


Top
 Profile  
 
 Post subject:
PostPosted: 25 Aug 2005 05:25 
i have had first hand experince here also. as one of mine broke. actually a fairly simple and good idea


Top
  
 
 Post subject:
PostPosted: 25 Aug 2005 14:40 
Offline
User avatar

Joined: 30 Nov 2004 23:24
Posts: 397
Location: Malaysia
Country: malaysia
that all good infos n learning about MIVEC engine and cool pictures too ...
so keep the updated n maybe next time cover other parts like block , pistons and others :)

Bart or Rabbit,
It would be nice if there is some JUN cams or high cam photos n explainations how they work basically 8)

thanks I hav learned about my MIVEC engine without openingit up :wink:

_________________
..............MiVeC GEN1 RoCkS .............


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 25 posts ]  Go to page 1, 2  Next

All times are UTC + 12 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 4 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
cron
Powered by phpBB® Forum Software © phpBB Group