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1970-1995 Range Rover Classic
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Discussion Starter #1
This is related to a '95 Classic with a RPI 4.6 where I was replacing the dizzy/coil and adding the RPI A&R amp. I know some folks have struggle with that setup and I may as well but there is an issue prerequisite that I need to sort.

Upon install of the new items, it would not start. Unfortunately, I did NOT note the dizzy's arm position and damper ring's stamped TDC position before removal of dizzy (just relied on the timing marks). Given the no start and suspecting the veracity of the damper outer ring timing marks (ie has it slipped?), I did the screwdriver in #1 to test for TDC/BDC and got two marks almost perfectly opposite one another (not a guarantee of either position but should be close). The results showed the stamped TDC mark is off 4+" from this test TDC for #1. Appears the outer ring on the crankshaft damper where the timing stamps are located has moved/slipped (and maybe moving still). While I think this is rare, I have seen other web discussions reference this. I made this new TDC #1 mark on both the outer timing ring and the main inner as the inner wont move (unless the woodruff key get sheared). Interested to see if these marks move at all in relation to one another (if they do, I know the issue).

My single conclusion is that the timing ring moved somehow as I can't put together a scenario where my reinstallation of the front cover last year could have caused this as there should be a permanent relationship between the TDC stamp on the damper ring and the woodruff key crank slot of same (unless it slipped), and a permanent relationship to this key slot and crank position (that cant change), and a permanent relationship to this crank position and TDC for #1 (fixed as well and cant change).

BUT, I'm always suspicious of Pilot error when I teardown and reassemble and something is awry but just cannot come up with a scenario where my reinstall would have moved the ring (seems impossible given the woodruff key slot). And of note, when removing the crank bolt, I always use the drop the pan/block of wood to journal method to loosed, not a huge pipe wrench on the dampener (which could have spun the ring). hopefully if i did something wrong, others will be able to see it as its hidden to me. Could it have happened wheeling (outer ring hits a rock and is momentarily torqued???) just don't know.

But if I'm correct, I guess the first concern is getting a new damper as if this current "slipped" timing damper ring comes off, there goes my new timing cover (which was very hard to come by) and a lot of other hard work is undone. Not sure if these crank dampers can be remanufactured as I don't think they are made anymore (ETC7339) (heard the rubber is frozen in nitrogen to install)

I was able to get the engine to start and idle properly using this new TDC mark and moving the dizzy back/forth and guessing where the advance was. However, that's not a comforting approach. point being as there is so little movement of the head at TDC I can't really say my new mark based on the screwdriver test is really true TDC (close but no guarantee). So, to this current timing issue, is there a timing tool setup (I just have the single strobe setup at present), that allows me to definitively peg TDC and set the advance without the benefit of the absolute true physical TDC mark?

Thanks for any help as my wife insists on keeping "ole Blue" on the road.
 

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There are a few well established tools out there to check you TDC location. They all require the removal of spark plug 1. There are little whistles that stop whistling at tdc etc.

The one I prefer is to take an old spark plug, hammer out the inside and put in a bolt/nut (see online) then you install and rotate from one direction till a stop (and mark) then from the other direction (and mark) your TDC is in-between the marks.
 

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I used a piece of cotton or a piece of tissue and put It in the spark plug hole of number 1 cylinder ... it pops out at tdc..on the compression stroke.... if I had not marked the dizzy...it also helps to have the valve cover off..
 

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1970-1995 Range Rover Classic
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Discussion Starter #4
think the valve cover is the only definitive method but a pita on the drivers side to remove if I'm not mistaken. I ordered a dial gauge with the 14mm to insert and test that way as I think that should be spot on way to hit TDC. I know I've got it close now.
 

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The drivers valve cover isn’t easy but it’s not hard eather...
But I get it...
 
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