disaster strikes?, valves too tight? |
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disaster strikes?, valves too tight? |
mattp |
Jul 3 2008, 09:34 PM
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#1
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Member Group: Members Posts: 257 Joined: 22-November 06 From: westchester NY Member No.: 7,252 |
I did my initial start up of my new raby engine, two of the cylinders had valves that were too tight causeing blow back throught the carbs. Adjusted valves and cant seem to make them any looser? any ideas?
also major oil leak from somewhere where engine meets transmission, thinking rear main seal?? |
LowGT |
Jul 3 2008, 09:59 PM
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#2
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1.8 and Proud! Group: Members Posts: 583 Joined: 2-October 05 From: Wylie, TX Member No.: 4,904 Region Association: Southwest Region |
I did my initial start up of my new raby engine, two of the cylinders had valves that were too tight causeing blow back throught the carbs. Adjusted valves and cant seem to make them any looser? any ideas? also major oil leak from somewhere where engine meets transmission, thinking rear main seal?? Are you sure the cylinder you were adjusting was at TDC? Other than that, not sure why you wouldn't be able to get slack. I had a similar leak, some was from the rear main, some was from the tranny input shaft seal (which later opened a whole other can of worms). But the majority of the leak came from the strainer gasket, the oil was running down the bottom of the engine and dripping off at the rear. Sometimes that finned oilpan hides a lot of oil. |
Borderline |
Jul 3 2008, 10:14 PM
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#3
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Senior Member Group: Members Posts: 720 Joined: 8-February 05 From: San Juan Bautista, CA Member No.: 3,577 Region Association: Northern California |
Who did the valve train setup and how were the pushrod lengths determined? If the 911 type swivel adjusters get really close to the rocker arm. If the pushrods were made a little too long you may not be able to to adjust the clearance properly. Also, when adjusting your valves you should use the method where you rotate the engine slowly and watch for valves to open. When one valve opens,stop and adjust the valve directly opposite...ie when the #1 exhaust opens adjust the #3 exhaust.
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mattp |
Jul 4 2008, 08:25 AM
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#4
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Member Group: Members Posts: 257 Joined: 22-November 06 From: westchester NY Member No.: 7,252 |
I had Raby do the pushrods before sending kit. I used the method you describe, it seemed easiest!
As far as the oil goes, its definetly coming from rear, no oil is around strainer. |
HAM Inc |
Jul 4 2008, 08:35 AM
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#5
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Senior Member Group: Members Posts: 846 Joined: 24-July 06 From: Watkinsville,GA Member No.: 6,499 Region Association: None |
Just to expand on what Bill said - When the #1 ex valve is at max lift then adjust the #3 ex valve. The key is making sure that the opposite valve is at max lift. That way you know that the lifter of the valve you want to adjust is on the heel of the cam.
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Jake Raby |
Jul 4 2008, 10:35 AM
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#6
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Engine Surgeon Group: Members Posts: 9,394 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States |
Matt's rocker geometry was completed by us during his extensive prep. It is correct.
Why can't you "make the valve looser"?? What is stopping you from the adjustment? It sounds like you are adjusting the valves at the wrong position, or I'd bet that the pushrods are not seated in the lifters correctly. You must use a flashlight to verify that each pushrod is seated in the lifter "cup" and isn't seating around that cup taking away 1/4" of valve adjustment. If this occurs bent valves are the norm from colliding with the pistons. Yes, if you have oil leaking at the tranny/engine then you either have made a goof installing the rear seal, or flywheel O ring or you have a galley plug leaking. Welcome to the world of engine building. We guaranteed you that it would be a challenge! BUT you do have support, it may be July 4th and I may be at home, but you can still call me. |
mattp |
Jul 4 2008, 12:11 PM
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#7
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Member Group: Members Posts: 257 Joined: 22-November 06 From: westchester NY Member No.: 7,252 |
I cant turn the adjuster any further. I backed it off as much as possible and before install I made sure they were seated. I will check again, but rotated engine by hand prior to starting it. What/ how could I have installed the rear seal? It seemed like one of the easier jobs to do! Common mistakes?
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SGB |
Jul 4 2008, 02:25 PM
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#8
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just visiting Group: Members Posts: 4,086 Joined: 8-March 03 From: Huntsville, AL Member No.: 404 Region Association: South East States |
Argghh. I feel your pain, bro. Dunno with the seal, but understand frustratrion.
It certainly sounds like the PR didn't seat, either at the lifter or the rocker... |
justme |
Jul 5 2008, 09:38 AM
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#9
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Member Group: Members Posts: 187 Joined: 1-January 07 From: southampton ma atlantic northeast Member No.: 7,413 Region Association: North East States |
Like Jake said,
Try pulling the rockers and checking the pushrods. If your backed off the adjusters and have no slack either your not a TDC or pushrods are not seated. Did you do a trial assembly? Any problems should have surfaced then,no?? GOOD LUCK!! (IMG:style_emoticons/default/beer3.gif) |
Jake Raby |
Jul 5 2008, 10:54 AM
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#10
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Engine Surgeon Group: Members Posts: 9,394 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States |
He didn't need a trial assembly... We did that for him with our extensive prep service.
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Borderline |
Jul 5 2008, 11:02 AM
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#11
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Senior Member Group: Members Posts: 720 Joined: 8-February 05 From: San Juan Bautista, CA Member No.: 3,577 Region Association: Northern California |
Were any shims left out? Cylinder or rocker shaft???
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Jake Raby |
Jul 5 2008, 11:39 AM
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#12
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Engine Surgeon Group: Members Posts: 9,394 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States |
When Matt and I talked yesterday I asked him all those questions.. He stated no...
For him to have no adjustment, the only thing that could have occurred was the pushrods not being seated fully into the lifters. Even with a rocker shim left out we allow enough adjustment to still have some "room" for adjustment. Matt was going to get back with me after he verified the pushrods were straight and after he got leak down numbers. My bet is he collided pistons into valves and coil bound the valve springs... If so it'll only be the second time that someone has made that mistake. Good thing we are shooting the assembly video net week, I can go over this in detail to keep it from happening for a 3rd time. |
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