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Discussion Starter · #1 ·
So the oil cooler line let go on my car and dumped all the oil out. I was not driving, but my gf noticed pretty quick and got it pulled off under a minute, but not before the loss of oil caused some damage to the internals of the motor. :eek:

I fixed the oil cooler line per the clamp method shown on this website and refilled her with fresh oil, but she ticks pretty back. Sounds like a sharp metalic tick that is tied to engine rpm. If the car had them, I would say it sounds exactly like a rocker arm gone bad. Almost like a diesel sounds at idle. Tick Tick Tick. It is coming from the top end of the motor.

The motor seems to run fine other than the ticking, but I have purchased a used motor as I will never trust this one having been run low on oil.

In the interim, before I pull and replace the old motor, I want to see if I can get it to stop ticking by replacing a few easy to replace parts.

1. How hard it is to replace the valve lifters? Is this a possible failure point that would cause this? Looking at the parts diagram, I can't see what else in the valve train would cause ticking like this. How hard are these parts to get out?

2. Is it possible it is the chain tensioner? Would this cause ticking?

Since I am a land rover guy, I am not too familiar with DOHC four cylinders and how to work on them.

I know others had similar issues with the oil cooler lines failing and then having motors that ticked, but those motors were replaced under warranty and I could not find anyone who tracked the ticking problem down. It seems to me that it is worth a shot to try to fix the ticking just to see what it is, even if I am going to replace the whole thing with a new motor.
 

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Discussion Starter · #3 ·
Humm, probably worthing looking at that too. Thanks. Did you get new cams? If so, what kind? What else was replaced?

Ron
 

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By your description of a diesel sound at idle, I wouldn't be too worried about a bad cam or follower, rather it sounds like you have a bad rod bearing from oil starvation. The easiest test is to have the car at idle with the handbrake on and your right foot firmly on the brake. Select 4th gear and very carefully ease out the clutch to the point where it just starts to grab (you are trying to load the engine yet keep it running) and listen for the banging/rapping noise to get louder. Do not release the brake for any reason during the test. If the noise gets louder or changes tone, you most likely have a worn or spun rod bearing and the engine will have to come out for a rebuild or replacement.

As far as the lifters go, this engine does not have hydraulic lifters and instead uses shims on the tip of the valve stem to set the valve to rocker clearances. The rockers are sold as a set with the cam and are not replaceable without replacing the cam as well.
 

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Discussion Starter · #6 ·
By your description of a diesel sound at idle, I wouldn't be too worried about a bad cam or follower, rather it sounds like you have a bad rod bearing from oil starvation. The easiest test is to have the car at idle with the handbrake on and your right foot firmly on the brake. Select 4th gear and very carefully ease out the clutch to the point where it just starts to grab (you are trying to load the engine yet keep it running) and listen for the banging/rapping noise to get louder. Do not release the brake for any reason during the test. If the noise gets louder or changes tone, you most likely have a worn or spun rod bearing and the engine will have to come out for a rebuild or replacement.

As far as the lifters go, this engine does not have hydraulic lifters and instead uses shims on the tip of the valve stem to set the valve to rocker clearances. The rockers are sold as a set with the cam and are not replaceable without replacing the cam as well.
Thanks!

It does not get louder when I drive it (if anything it gets a little quieter) it only gets faster with RPM. It seems to be very clearly coming from the top of the engine, but I do know engine noises travel. I will try your test tonight. It is not really a knock (like a diesel) it is really a tick.

What number are the "rockers" in this diagram (ie what else are they called)"

Conicelli Parts Center

Ron
 

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Listen to the speed of the tick. The cam turns at 1/2 crank speed so lifter or cam noise is slower. If you suspect a rod bearing killing spark or fuel to the suspect cylinder will make the noise change.
 

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Discussion Starter · #8 ·
How do I know what is fast or slow for ticking? About how many ticks per second indicates a cam v. a rod?

Ron
 

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Thanks!

It does not get louder when I drive it (if anything it gets a little quieter) it only gets faster with RPM. It seems to be very clearly coming from the top of the engine, but I do know engine noises travel. I will try your test tonight. It is not really a knock (like a diesel) it is really a tick.

What number are the "rockers" in this diagram (ie what else are they called)"

Conicelli Parts Center

Ron
I don't see the rockers in that diagram, but they are items 6 and 7 in this one: Lotus Garage - Camshafts, Tappets, Cam Cover

If you are still suspecting a cam or rocker failure, just remove the valve cover and have a look at the parts. It is really easy to do.
 

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Discussion Starter · #10 ·
I can just pull all that stuff out after removing the valve cover? Anyone do a write up? On a push rod motor I could do it easily, but with the DOHC I have this fear the whole thing will get out of time or something.
 

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I can just pull all that stuff out after removing the valve cover? Anyone do a write up? On a push rod motor I could do it easily, but with the DOHC I have this fear the whole thing will get out of time or something.
I have a write up (Word document) on in the car cam/follower replacement on my computer at home I can send you, but I won't be leaving work until after 10:00 PM today. If you want me to send it to you, just PM me your email address and I'll send it late tonight.
 

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By your description of a diesel sound at idle, I wouldn't be too worried about a bad cam or follower, rather it sounds like you have a bad rod bearing from oil starvation. The easiest test is to have the car at idle with the handbrake on and your right foot firmly on the brake. Select 4th gear and very carefully ease out the clutch to the point where it just starts to grab (you are trying to load the engine yet keep it running) and listen for the banging/rapping noise to get louder. Do not release the brake for any reason during the test. If the noise gets louder or changes tone, you most likely have a worn or spun rod bearing and the engine will have to come out for a rebuild or replacement.

As far as the lifters go, this engine does not have hydraulic lifters and instead uses shims on the tip of the valve stem to set the valve to rocker clearances. The rockers are sold as a set with the cam and are not replaceable without replacing the cam as well.
Agreed....this happened to me....loss of oil resulting in rod/bearing failure.

I had to replace the short block - at the same time, I updated valve springs (which are a common point of failure)....
 

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Discussion Starter · #14 · (Edited)
Can I pull the bearing caps off if I remove the oil pan? Bearing sets are $14, it might be worth installing a set in situ (you can do this on a rover so maybe I can do it on a lotus :))

Ron

Would it be a rod bearing if it goes away on the second cam? Is that a way to tell if it is a rod bearing?
 

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Before you tear down your engine...

I once put in too much oil during an oil change. The engine ticked for a while until I took out about 1/4 quart of oil--tick went away. Perhaps you have too much oil in the engine.
 

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Discussion Starter · #16 ·
So it took a while (I worked for 93 straight days which killed the summer driving weather so I waited until this spring to finish the job), but I replaced the motor. I will tear down the old one at some point to see what the failure actually was, but for the price of a used motor I figured I would just swap it.

:UK:
 

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+1

By your description of a diesel sound at idle, I wouldn't be too worried about a bad cam or follower, rather it sounds like you have a bad rod bearing from oil starvation. The easiest test is to have the car at idle with the handbrake on and your right foot firmly on the brake. Select 4th gear and very carefully ease out the clutch to the point where it just starts to grab (you are trying to load the engine yet keep it running) and listen for the banging/rapping noise to get louder. Do not release the brake for any reason during the test. If the noise gets louder or changes tone, you most likely have a worn or spun rod bearing and the engine will have to come out for a rebuild or replacement.

As far as the lifters go, this engine does not have hydraulic lifters and instead uses shims on the tip of the valve stem to set the valve to rocker clearances. The rockers are sold as a set with the cam and are not replaceable without replacing the cam as well.
that is exactly what I had when my return line blew........so no need for a new engine......just new bearings
 

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If the bearings are toast so is the the crankshaft and the connecting rod on that cylinder!!! It can/will also score the cylinder from all of the bearing shrapnel being thrown on the bottom of the piston!

As a former engine builder I know all it takes is seconds without oil and its toast! once its knocking it's done!

I have seen an engine in a SCCA D sports racer fail from 1 tenth of a second oil starvation! And it through all 4 rods out of the block 2 laps later
 
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