Cooling fan ?, Anyone know the degrees per blade? |
|
Porsche, and the Porsche crest are registered trademarks of Dr. Ing. h.c. F. Porsche AG.
This site is not affiliated with Porsche in any way. Its only purpose is to provide an online forum for car enthusiasts. All other trademarks are property of their respective owners. |
|
Cooling fan ?, Anyone know the degrees per blade? |
ottox914 |
Feb 17 2006, 09:41 PM
Post
#1
|
The glory that once was. Group: Members Posts: 1,302 Joined: 15-December 03 From: Mahtomedi, MN Member No.: 1,438 Region Association: Upper MidWest |
Messing around with some updates to the 914, no problem finding TDC, but my other timing marks are hard to find. As a means to double check my work, anyone know how many degrees per fan blade? Yes, I've tried Mr Search to no avail.
|
Dave_Darling |
Feb 17 2006, 10:15 PM
Post
#2
|
914 Idiot Group: Members Posts: 15,000 Joined: 9-January 03 From: Silicon Valley / Kailua-Kona Member No.: 121 Region Association: Northern California |
Check the photos in the "914 timing" article on the Pelican site. You can see where the marks are in relation to the fan blades. There's also a template you can print out...
--DD |
ottox914 |
Feb 18 2006, 07:37 AM
Post
#3
|
The glory that once was. Group: Members Posts: 1,302 Joined: 15-December 03 From: Mahtomedi, MN Member No.: 1,438 Region Association: Upper MidWest |
Good answer dave, but not exactally what I was looking for. I was probably a little vague, so I'll try to ask again with more info-
I'm installing an aftermarket efi system, (I'll post details once it runs) and don't need to know where the stock timing marks are. I know where TDC is, but need to set a base timing different than a factory referened mark on the fan. As I know where TDC is, how many degrees are referenced per fan blade, so I can approximate where and what my timing is being set at, since I don't need/can't use the factory timing marks? |
Mark Henry |
Feb 18 2006, 09:01 AM
Post
#4
|
that's what I do! Group: Members Posts: 20,065 Joined: 27-December 02 From: Port Hope, Ontario Member No.: 26 Region Association: Canada |
What system are you running? I take it you have some sort of programmable ignition?
On my SDS I made a mark at 10 degrees BTDC that you saw through the timing hole in the fan shroud. You then started the engine and at idle you set the baseline crank-fire timing with a strobe. After that you use the program to set your timing. Guessing at fan blades is a poor method for setting the baseline. |
swl |
Feb 18 2006, 09:27 AM
Post
#5
|
Senior Member Group: Members Posts: 1,409 Joined: 7-August 05 From: Kingston,On,Canada Member No.: 4,550 Region Association: Canada |
The template on the pelican site is great tool. You can use it to do a much better job estimating degrees than blades would. That said, the diagram on pg65 of the haynes manual is pretty accurate I think shows 4.5 blades in 27degrees.
|
Jake Raby |
Feb 18 2006, 10:36 AM
Post
#6
|
Engine Surgeon Group: Members Posts: 9,394 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States |
Pop out the number one spark plug and the corressponding valve cover.. Rotate the engine clockwise until the intake valve on #1 opens fully and then closes fully.
Then use a drinking straw in the spark plug hole to feel the piston as it travels up the bore to TDC. When you have found the point where the piston is highest and dwells there for a second that is TDC, remove the timing plug and using a nling, sharp chisel or screw driver stamp a mark. You are done and within a degree of where TDC really is if you do the job accurately. BTW, there are 4 different 914 fans- you can't use the blade method due to this unless you are a half asser! |
Mueller |
Feb 18 2006, 10:47 AM
Post
#7
|
||
914 Freak! Group: Members Posts: 17,146 Joined: 4-January 03 From: Antioch, CA Member No.: 87 Region Association: None |
actually, Daves answer was spot on (IMG:http://www.914world.com/bbs2/html/emoticons/smile.gif) what you "you" need to do is print out the template (make sure it's 1:1) lay it on the fan and measure how many degrees from one blade to another with the template...measure the diameter of the fan and just do the math...Dave Hunt also posted a link to a downloadable degree wheel that'll help with the setup as well.... |
||
McMark |
Feb 18 2006, 11:42 AM
Post
#8
|
914 Freak! Group: Retired Admin Posts: 20,179 Joined: 13-March 03 From: Grand Rapids, MI Member No.: 419 Region Association: None |
How about an adjustable timing light? Then you only need to know TDC. (IMG:http://www.914world.com/bbs2/html/emoticons/confused24.gif)
|
spare time toys |
Feb 18 2006, 11:47 AM
Post
#9
|
hooked on grilling food. Group: Members Posts: 4,059 Joined: 3-April 04 From: West Plano Tx Member No.: 1,884 Region Association: Southwest Region |
Cant you count the number of blades and devide 360 by that number to get how many degrees of rotation it would take to move 1 fan blade? Like if you have 10 blades it would take 36Deg. of rotation to move one blade.
|
Cap'n Krusty |
Feb 18 2006, 12:02 PM
Post
#10
|
Cap'n Krusty Group: Members Posts: 10,794 Joined: 24-June 04 From: Santa Maria, CA Member No.: 2,246 Region Association: Central California |
Measure the circumference of the fan, divide by 360. That'll give you the exact length of each degree. Based on the number of degrees you need, measure the distance and mark it. How hard can that be? The Cap'n
|
davep |
Feb 18 2006, 06:22 PM
Post
#11
|
||
914 Historian Group: Benefactors Posts: 5,162 Joined: 13-October 03 From: Burford, ON, N0E 1A0 Member No.: 1,244 Region Association: Canada |
No, there are posts and there are blades. I don't think there is an equivalence between posts and blades that is useful. |
||
alpha434 |
Feb 18 2006, 06:53 PM
Post
#12
|
My member number is no coincidence. Group: Members Posts: 3,154 Joined: 16-December 05 From: Denver, CO Member No.: 5,280 Region Association: Rocky Mountains |
. 8.875
(diameter)/2=4.4375(radius) - 2in (sector)/2 = 1 - 1/4.4375 = inv SIN 13.02 deg. X 2 = 26.04 deg. |
alpha434 |
Feb 18 2006, 06:54 PM
Post
#13
|
My member number is no coincidence. Group: Members Posts: 3,154 Joined: 16-December 05 From: Denver, CO Member No.: 5,280 Region Association: Rocky Mountains |
That's measured along the circumference. Just use a tape measure and you'll be close.
(IMG:http://www.914world.com/bbs2/html/emoticons/cool.gif) 2 inches= 26deg |
Lo-Fi Version | Time is now: 29th June 2024 - 07:31 AM |
All rights reserved 914World.com © since 2002 |
914World.com is the fastest growing online 914 community! We have it all, classifieds, events, forums, vendors, parts, autocross, racing, technical articles, events calendar, newsletter, restoration, gallery, archives, history and more for your Porsche 914 ... |