Mechanics

NEED TO KNOW WHERE TIMING MARKS AND ROTOR SHOULD POINT AND TOP DEAD CENTER

1986 Nissan Truck • 125,000 miles

I am working on a 1986 nissan 4x4 pickup with a 2.4 TBI whom some one else took the cylinder head off and did not paint or mark the links on the chain or cam sprocket before removal, however I am stuck with putting it back together. According to manuals, there should be 2 discolored chain links {NOT SO}!Every time I get it on TDC on compression stroke, the distributor rotor points toward #4cyl on the intake side even though both the intake&exhaust valves are both closed.I have the camshaft dowel facing vertical with the #2 at TDC compression stroke.I have not tried to start it in fear of bending valves. However I have manually turned the engine over by hand and cant detect any valve to piston interference. Can someone show me a clearified diagram of the 2.4 {8 sparkplug}timing, cam gear at TDC?Thanks!
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Craigcooper
October 10, 2012.




Installation

1. Ensure No. 1 cylinder is at TDC on compression stroke. Install crankshaft sprocket, oil pump drive gear and oil thrower (if removed). Mating marks on crankshaft sprocket must face front and large inner chamfered area of oil pump drive gear must face engine rear.

2. Place timing chain on camshaft sprocket. One Silver colored link on chain must be aligned with No. 2 dot on outer camshaft sprocket. The Second Silver link on chain must align with dot on crankshaft sprocket.

3. Install camshaft sprocket and timing chain. Ensure No. 2 hole on camshaft sprocket is fitted to camshaft knock pin. Install timing chain guide and tensioner on right side of timing chain. Ensure chain guide is installed tight against chain.

4. Install chain guide on left side of timing chain. Adjust the protrusion of chain tensioner and chain guide to zero. To complete installation, reverse removal procedure. With components installed, slowly rotate crankshaft to ensure pistons do not interfere with valves.

The so called silver links could be slightly darker in shade. I they are covered in oil, it would be difficult to distinguish, wipe them clean and dry and you shold be able to differentiate.

I could not find any reference on the distributor installation but what you have would mean the distributor is 180 degrees off. Before you do anything, ensure the # 4 cylinder valve are overlapped.

TDC can mean beginning of compression or intake stroke.

If markings are correct and distributor needs to be reinstalled, pull it out. There is a punxh mark on the distributor end gear. On housing there is a detent or triangular arrow mark. Match the two points and you have the rotor at # 1 firing position. Plug distributor in, remember to note the position of the holding bolt. The rotor would turn slightly when it goes in due to the gear sliding in.
With # 1 cylinder at TDC on compression stroke.


KHLow2008
Oct 10, 2012.
One more diagram for you.
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KHLow2008
Oct 10, 2012.
First off, I thank you for your help. I am sorry I am not currently in a position to donate any funds at this time. It wont be until this weekend until I get back to it.I do know that the wiring diagram you provided is different than the chilton manual. It shows #1 intake to be where your diagram shows#4E to be. Is it possible someone has rewired the distributor previously, and I am paranoid. Because as I have it, I could not feel any valve to piston interference.I have compression, both intake&exhaust valves are closed, and according to the diagram you provided, this engine, the rotor points toward 2e and thats where the #1I wire is at.


Tiny
Craigcooper
Oct 10, 2012.
Guess someone had the timing wrong by a tooth or two and decided to change the location of the # 1 cylinder. It is ok, it would still work without any problem. Important thing is the timing chain is installed correctly.


KHLow2008
Oct 11, 2012.

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