| Author |  Topic  | |
frank
V4 Fan
United Kingdom
128 Posts |  Posted - 20 Jul 2010 : 18:07:56  
| | My ballance shaft gear is starting to clatter,is it worth trying to do the job with the engine in ,or is it best to take the engine out. Frank. |
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melle
V4 Fan
Netherlands
171 Posts | Posted - 20 Jul 2010 : 19:17:50
| Never thought about this option. Forgot whether you remove a balance shaft from front or rear. If it is to be removed from the front, why not give it a try? When you remove grill and rad there's plenty of room I would say.
1970 Saab 96V4 "The Devil's Own V4"
1974 Saab 95V4
1977 Saab 95V4 van conversion project |  |
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Woody
V4 Guru
United Kingdom
1210 Posts | Posted - 20 Jul 2010 : 19:26:03 
| | Cannot to do in situe. Balance shaft is withdrawn from the rear so you need to remove engine. If you have any lateral movement at the pulley then the bearing has worn or is starting to break up. Check for the backlash at the pulley as if left the gear might strip. Have you got an oil leak here too as this is a sure sign of wear as the shaft is moving and wears the seal? | |
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pchristy
V4 Mad
United Kingdom
511 Posts | Posted - 20 Jul 2010 : 19:40:15
| Also, what is your tick-over oil pressure? As long as its over 2olb/sq.in (preferably 25!) you are probably OK.
First sign of the balance shaft bearings going is the oil light coming on at tick-over (from experience!).
These engines do clank a lot from the front! They were like that when they left the factory! (Also from experience!)
--
Pete
"Duct tape is like the Force: It has a light side and a dark side, and it binds the Universe together!" | |
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melle
V4 Fan
Netherlands
171 Posts | Posted - 20 Jul 2010 : 21:12:20
| quote:
Originally posted by Woody
Balance shaft is withdrawn from the rear so you need to remove engine.
Was afraid so..
1970 Saab 96V4 "The Devil's Own V4"
1974 Saab 95V4
1977 Saab 95V4 van conversion project | |
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rsimps
V4 Mad
United Kingdom
957 Posts | Posted - 21 Jul 2010 : 07:34:17
| You can change the gear by taking the front cover off and dropping the sump down at the front (try not to damage the sump gasket). As stated above, the usual cause for worn gears is a worn bearing and for this the shaft needs to come out of the back. You can lift the engine up and move it forward within the engine bay and take the shaft back enough to replace the front bearing, but you might as well pull the whole thing out and do the job properly at this point.
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frank
V4 Fan
United Kingdom
128 Posts | Posted - 21 Jul 2010 : 08:32:59
| | So i can check the wear on the ballance shaft gear teeth,How much back lash is too much in the front pulley? Also if there is no movement up and down in the ballance shaft baerings, is it worth changing the gear. Frank. | |
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john-saab
Moderator
United Kingdom
800 Posts | Posted - 21 Jul 2010 : 12:07:05
| Do not assume that because there is no up and down or side to side movement in the balance shaft that it is in good condition...mine didn't move but that was because the surface to the white metal bearing had peeled away and was jammed up against the balance shaft face..it felt good but when i removed it i found this..
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melle
V4 Fan
Netherlands
171 Posts | Posted - 21 Jul 2010 : 15:18:25
| Hmmm, looks familiar unfortunately, some time ago though. I would test the oil pressure first. For timing gears examination also see Haynes manual page 29. When replacing timing gears always replace full set.
1970 Saab 96V4 "The Devil's Own V4"
1974 Saab 95V4
1977 Saab 95V4 van conversion project | |
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frank
V4 Fan
United Kingdom
128 Posts | Posted - 21 Jul 2010 : 17:07:05
| | My first engine had no play in the pulley but it took the teeth off the ballance shaft gear,i thank i will do an oil pressure test,is it minimum 20psi at tick over on a HOT engine or COLD? Frank. | |
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pchristy
V4 Mad
United Kingdom
511 Posts | Posted - 21 Jul 2010 : 19:56:54
| When mine failed 30 years ago (!) the oil pressure dropped to almost zero at tick-over - hot or cold! It was enough to bring the warning light on!
Luckily, I investigated before the gears went!
My current engine (a Vege rebuild with about 20K miles on it) shows around 25 psi hot at tick-over, though this can briefly drop to 20 after a long motorway stint. It quickly recovers once you get into traffic. That is running on 15W-40. It will vary a bit with oil manufacturers. Back in the day, Shell 20-50 (there was no 10 or 15-40 then!) used to hold its pressure best when hot. I've just tried their current 15w-40, and its no different from the Comma stuff I was using previously.
I don't know how this compares with what others get?
BTW, the original (new, blue engine) '69 car NEVER showed more than 45 psi, even when stone cold! Mostly it hung around 40 psi at speed, dropping to 28 ish at tick-over. My current car shows a steady 60 psi above 1500 rpm, and even reaches 80 when cold, dropping to 25 at tick-over (hot).
I have no idea if its got an uprated pump or not! How do these figures compare with what others get?
--
Pete
"Duct tape is like the Force: It has a light side and a dark side, and it binds the Universe together!" | |
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john-saab
Moderator
United Kingdom
800 Posts | Posted - 21 Jul 2010 : 21:23:15
| And to add to the confusion..once you have tested the engines oil pressure..start again!
I had a Smiths oil pressure gauge..a good looking old unit and it read 25psi on tick over. I tried a TIM unit..(modern horrible looking thing) on the same engine and it read 45psi on tick over..tried another un-named old pressure gauge (made in Japan stamped on the back) and it read 40psi at tick over.
Moral of the story..buy a new top quality oil pressure gauge and assume it is correct! | |
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frank
V4 Fan
United Kingdom
128 Posts | Posted - 22 Jul 2010 : 09:29:00
| | Thanks for the tips ,i will be back soon with the results,i could be lucky this time. Frank. | |
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frank
V4 Fan
United Kingdom
128 Posts | Posted - 22 Jul 2010 : 12:55:06
| | Hi 38psi hot engine on tick over on a snap on tool,my conclusion is that the first engine was the same as Johns,no movement in pulley as bearings were so worn they were tight,the current engine good oil pressure ,clatter at the front is normal as mentioned earlier,i do feel more confident now that i have done the oil pressure test.Thanks for the tips Frank. | |
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melle
V4 Fan
Netherlands
171 Posts | Posted - 22 Jul 2010 : 13:07:52
| I've long planned on installing oil pressure gauges in all of my cars, but it never happened for some reason. Reckon it would be good to be able to monitor the oil pressure at all time.
1970 Saab 96V4 "The Devil's Own V4"
1974 Saab 95V4
1977 Saab 95V4 van conversion project | |
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Jon
V4 Beginner
France
60 Posts | Posted - 25 Jul 2010 : 11:18:56 
| I had an incident on a motorway where after a spell of driving too fast (for the poor old engine) the balance shaft gear mashed up on me - I had always wondered what the engine would be like at 90mph without balance correction!! I managed to abandon the car at a friendly garage and the next day I came back with my tools + spare gear and changed the gear in situe.
I have to admit it was a hash job, after ripping off the front cover and sump and not being able to clean the surfaces properly (I had to use a whole tube of gasket sealant to botch up things) it would have been easier to just pull the enine out - although I didn't have an engine hoist to hand...
Jon
http://www.dutton.co.uk/saab/ | |
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| | Topic | |
ballance shaft gear
