Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help

Go Back   PeachParts Mercedes ShopForum > Technical Information and Support > Tech Help

LinkBack Thread Tools Display Modes
Old 01-02-2002, 11:59 AM
pmizell's Avatar
Benz Zealot
Join Date: Jun 2001
Location: Houston, Texas
Posts: 838
valve guides M103

Need an educated guess here. The machine shop reconditioning my head and valves needs parts with head to expedite the service.

My question is, which size valve guides should I order if my engine is not burning oil? There's the standard size, then a slightly oversize guide I assume that's needed when guides start to rattle around -- not my case I don't think.

Do you think the standard size would press in fine on a 206,000 mile engine?



'91 300E, 206k miles
Reply With Quote
Old 01-02-2002, 12:53 PM
Join Date: Mar 1999
Location: Tucker, Ga USA
Posts: 12,153
UNLESS the guides "fall" out of the cylinder head always use the std size! The oversize is OUTSIDE dia. not the inside.
MERCEDES Benz Master Guild Technician (6 TIMES)
ASE Master Technician
Mercedes Benz Star Technician (2 times)
44 years foreign automotive repair
27 Years M.B. Shop foreman (dealer)
MB technical information Specialist (15 years)
190E 2.3 16V ITS SCCA race car (sold)
1986 190E 2.3 16V 2.5 (sold)
Retired Moderator
Reply With Quote
Old 01-02-2002, 01:47 PM
Join Date: Mar 2000
Location: Gainesville FL
Posts: 6,844
The key with guides is an appropriate interference fit as they are pressed in. As it turns out the standard guides are oversize anyway. Years ago the the true standard guides were available. As example a the outside diameter of your guides will be about 14.01mm. The standard replacement will be 14.05mm. The guides are also available in 14.20mm and 14.40mm.

If a guide is loose in the head or assembles too easy then a larger guide is necessary. I think MB would have you broach the hole in the head to the appropriate ID. This is a very dangerous procedure as there is no going backward. An old MB tech told me 25 years ago how to do it safely. You cut the larger guide to a little bigger than the hole on a lathe (this sometimes requires trial and error with the loss of a guide or two). Then you drive it in with at least as much force as the good ones (since the hole is deformed a tighter than normal fit will be required). The head hole will be slightly ovalled and the guide will be forced to the shape. They won't come out. After this the inner diameter must be sized by reaming to the proper diameter.

The added size of the new guides will work in all holes that the old guides were firmly installed.
Steve Brotherton
Continental Imports
Gainesville FL
Bosch Master, ASE Master, L1
33 years MB technician
Reply With Quote
Old 01-11-2002, 12:26 AM
Senior Member
Join Date: Jun 2001
Location: Northern Calif. (Fairfield Area)
Posts: 2,225

It's quite simple.Either you are dealing with an unqualified machine shop or you're getting in the middle of things.If they tell you what they need, trust them to do their job.If they're asking you for advice find another machine shop.A good experienced machinist can measure accurately and tell you what fits in what hole.Hope this helps.

Auto Zentral Ltd.
Reply With Quote
Old 01-11-2002, 08:56 AM
Registered User
Join Date: Aug 2001
Location: secret
Posts: 3,044
What are the clearances for valvestem to guide on the M103?
Reply With Quote
Old 01-11-2002, 11:29 AM
Senior Member
Join Date: Jun 2001
Location: Northern Calif. (Fairfield Area)
Posts: 2,225

Don't know exactly,but it doesn't matter because you can't measure clearances with the valve train intact.With the head off the car and the springs off,you could check latteral movement witha dial indicator.The most accurate test is to remove the valve and slide what's called a go no go gage in the hole.If the no go end slides into the guide, it needs to be replaced.
Auto Zentral Ltd.
Reply With Quote


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On

Similar Threads
Thread Thread Starter Forum Replies Last Post
Valve cover gasket replacement 95 E320. 71Rcode Tech Help 0 03-10-2004 08:44 PM
Schrick M103 Camshaft with Valve Springs AMGmercedes Mercedes Used Parts For Sale & Wanted 1 02-20-2004 08:32 AM
2 used m103 valve covers mb*docc Mercedes Used Parts For Sale & Wanted 4 11-20-2003 03:48 PM
M103 91 300SE idle air valve sixto Tech Help 12 10-27-2003 05:23 AM
Valve Stem Seals Sucessfully Replaced John Plut Tech Help 21 04-18-2002 11:08 AM

All times are GMT -4. The time now is 03:00 PM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2018, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2018 Pelican Parts LLC - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page