Home 
Home Search search Menu menu Not logged in - Login | Register
> Jensen Healey & Jensen GT Tech > Engine & Transmission > Tming marks

 Moderated by: Greg Fletcher
New Topic Reply Printer Friendly
Tming marks  Rate Topic 
AuthorPost
 Posted: 11-20-2006 04:22 pm
  PM Quote Reply
1st Post
smcmanus
Member


Joined: 03-08-2006
Location:  
Posts: 123
Status: 
Offline
 This picture taken with engine at TDC at the no. 1 cylinder.  Engine #7306. Is this correct?

The cams seals look to have been leaking.  Anyone have the seal numbers?  I'm changing all of them.

Attachment: JHcams.jpg (Downloaded 81 times)

Last edited on 11-20-2006 04:27 pm by smcmanus
Back To Top PM Quote Reply  

 Posted: 11-20-2006 04:25 pm
  PM Quote Reply
2nd Post
smcmanus
Member


Joined: 03-08-2006
Location:  
Posts: 123
Status: 
Offline
 Also at TDC, this is what the crank pulley looks like.  The crank timing marks seem dorked up.  Neither the crank or the cam timing marks seem to match what I see described in the book. 

Thanks

Steve

Attachment: JHtimingmarksdorkedup.jpg (Downloaded 67 times)
Back To Top PM Quote Reply

 Posted: 11-21-2006 04:31 am
  PM Quote Reply
3rd Post
Mark Rosenbaum
Member


Joined: 03-12-2005
Location: Kingman, Arizona USA
Posts: 532
Status: 
Offline
 Cam timing is discussed in section A52 of the shop manual as well as other locations in the factory documentation.  What they tried to say is:
  • 100 IN / 110 EX - North American engines only, #10480 up only (meaning T-prefix air pump engines).  JHs and GTs with this cam timing typically run poorly compared to earlier cars.
  • 110 IN / 110 EX - Engines #4040 to #10479, and #10480 up for other than North America.
  • 115 IN / 115 EX - Engines #4039 and below.
Your engine #7306 should be set to 110 IN / 110 EX.  Since your photo shows 115 IN and unknown EX, the cam timing is not correct.  It will run that way but performance may suffer.  You can get the correct timing without spending money on parts as the gears are reversible.  WARNING: considerable care must be used to avoid bending your valves.  This was a hot topic for a while on the old JHPS site, so a search there should be beneficial.  I think there's a decent cam timing procedure in there somewhere, too, but it's been years and I could be wrong.

I've attached an annotated photo of two identical cam gears with their different faces showing.  This should clarify how most gears are marked.  Some folks have trouble picturing how things should be arranged, however, so for them I suggest printing out the photo, cutting out the two gears and arranging their pictures for the proper timing, then making the car look like the arrangement.  Paper dolls, yes, but it works.

As for your crank pulley and its timing marks, possibly a PO added additional marks for some unknown reason.  I would try to determine whch of the marks actually was TDC before doing anything else, specifically including altering the cam timing.  This can be a bit tricky to determine, as the #1 piston moves only 0.026" from 10°BTDC to TDC, but with repeated attempts it should be possible to make an accurate determination.  Then just put a daub of paint on the correct notch in the pulley. 

If you have trouble with any of the above, contact me directly and I'll see what I can do to provide a bit of guidance.  Good luck

Attachment: cam gears annotated.jpg (Downloaded 78 times)
Back To Top PM Quote Reply  

 Posted: 11-21-2006 11:23 am
  PM Quote Reply
4th Post
smcmanus
Member


Joined: 03-08-2006
Location:  
Posts: 123
Status: 
Offline
 Thanks again!  I'm glad I asked. 

Steve
Back To Top PM Quote Reply

 Posted: 11-21-2006 06:30 pm
  PM Quote Reply
5th Post
smcmanus
Member


Joined: 03-08-2006
Location:  
Posts: 123
Status: 
Offline
 Mark et al

I pulled the pulleys.  The one marked Lotus with only in and ex on apposing sides matches with the 110 in and 110 ex marks on the other pulley.  Seems like I should be able to figure that out.

As for seal numbers?  Anybody got them or do I need to order from Delta?

Thanks

Steve

 
Back To Top PM Quote Reply  

 Posted: 11-21-2006 06:46 pm
  PM Quote Reply
6th Post
Mark Rosenbaum
Member


Joined: 03-12-2005
Location: Kingman, Arizona USA
Posts: 532
Status: 
Offline
 I don't have an industry standard number for the cam seals, but Delta should have them in stock.  It's fairly easy to remove the old ones and install the new ones, but you do have to be certain not to rotate the cams while doing so.
Back To Top PM Quote Reply

 Posted: 11-22-2006 01:13 am
  PM Quote Reply
7th Post
Sylva
Member
 

Joined: 09-14-2006
Location: Malaysia
Posts: 54
Status: 
Offline
 Mark

great picture, is the same true for the latter HTD 9round tooth) pulley?

Thamks for info
Back To Top PM Quote Reply  

 Posted: 11-22-2006 01:18 am
  PM Quote Reply
8th Post
Mark Rosenbaum
Member


Joined: 03-12-2005
Location: Kingman, Arizona USA
Posts: 532
Status: 
Offline
 Don't know as I've never seen a car using the HTD system.  However, I understand that there are several owners here that use it, and perhaps one of them would be kind enough to post photos. 
Back To Top PM Quote Reply

 Posted: 11-22-2006 01:37 am
  PM Quote Reply
9th Post
Sylva
Member
 

Joined: 09-14-2006
Location: Malaysia
Posts: 54
Status: 
Offline
 I'll check the weekend, I have afew ses of squar wheels, and my HTD wheels ar f the car, so I can line up the key ways and see.
Back To Top PM Quote Reply  

Current time is 12:11 pm  
> Jensen Healey & Jensen GT Tech > Engine & Transmission > Tming marks Top


UltraBB 1.172 Copyright © 2007-2011 Data 1 Systems