I broke my engine :(

I think I have spares, if you haven’t already ordered them.

Let’s see, let me try to walk through what I did. I had the cams aligned and chain on, but the crank shaft carat not aligned. Looked again for the carat (haven’t rotated engine or anything), found the carat. Took the chain off, then rotated the engine to line up crank shaft carat to the bottom edge of the pointer. Lined up the camshafts using the alignment tool and put the chain on starting with intake side sprocket and rotating the slack towards exhaust side, there was very little to no slack when I put the other (exhaust side) sprocket on.

Thanks for the offer jitneybead, I’m going to order some freeze plugs off SNG barat as well

I understand there was likely not much “noticeable” slack, but Again… did you put tension on the on the tensioner before you put on the exhaust sprocket?
In order to access all four bolts on each cam, you had to have rotated the engine, and in Righty-tightening those 8 bolts and tapping down the stays, you could have introduced the slack that sounds like it showed up on the intake side.

I did not put tension on the chain when tightening the sprockets, I did have some pliers clamped on the camshaft “rod” to hold the camshafts still. I used different wrenches when accessing those 8 bolts, so I don’t believe I rotated the engine at all when tightening. To get the holes lined up for the sprockets I just kept rotating them with the chain off until it linend up. Either way looks like I’ll be taking the chain off again though

As of right now, there is zero slack in the chain, I’m assuming that because I tried starting the car earlier last week

Could you take a picture of how far “off” you are on the intake side? It seems like the most likely culprit, but maybe not.
I think its is very important to have tension on the exhaust side of the chain when reassembling. You have to have slack in the “left” exhaust side when setting the “right” intake side, then apply the tension on the exhaust to simulate a running condition.

I applaud you for having the patience to put all eight bolts and tabs without turning the engine or dropping anything. But… if you have the top dead center identified - the caret, the rotor pointing at the 1 notch in the distributor, the cams aligned, and slack removed from the right/intake, you can safely turn it by hand - and check that you are putting enough tension on the left to keep everything aligned as you tighten everything up.

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Thanks for the advice, that makes since about rotating the engine - I’m assuming you attached both sprockets with the top 2 bolts and rotated the engine to install the other bolts? I didn’t think of that. Here are the pictures I took right now. Let me know what you think

Oh, yeah. That’s your problem.
Chain off and do it all again,
But the good news IMO is that I don’t think that amount of “off” would cause the valves to smack into each other and bend them.

So yes, you need to find all of your marks with the sprockets off. Be careful rotating the cams independently - from the looks of it, you can reset them with the chain off with a small rotation.

As I indicated above (and in the manual) when you move the exhaust side after setting the intake side, you need to put tension on the tensioner. Only then put the outer sprocket on and “find” where holes line up using the tiny teeth. You’ll have slack no on the right side, no slack between the sprockets and pressure against the chain while at the same time the caret is line up at the indicator. (where the rotor points is less exact since you can a) rotate the distributor a bit and b) the ecu handles timing away.
Lightly tighten up the top two bolts to secure it. This should solidly assign everyone’s final position. Its an opportunity to rotate the engine over through its firing order before hard tightening.

I would suggest that if you have a socket for the crankshaft (I’m assuming you been using one all this time) you go ahead and put it on as you are tightening the sprocket bolts and tapping down the stays. It will require some gymnastics but you can provide lefty “opposing support” via the crankbolt as you securely righty tighty the sprocket bolts.

You’re so close, man!


Thank you for the tips Jitneybead, hopefully my intake cam being off is what is causing my issue. My parts won’t come in for 1-2 weeks so I won’t be able to work on it until then.

Well tried again and got the same results :(. My engine just sounds broken, only starts and stays running if you tap the gas, once you let go of the gas it the engine dies. Anyone in Arizona want to buy an XJ6? Don’t want to junk the car

will do a compression test tomorrow

My cylinder five is at 120psi and cylinder 4 is at 140ish psi while my other cylinders are at 150ish PSI, before this “repair” job all cylinders where at 150PSI

An engine needs three things to run properly. Air, fuel, spark. Have you checked all air related parts? Clean air filter, MAF, no vacuum leaks, idle speed motor, oxygen sensor. Do you have the required fuel pressure? Are all plugs giving sparks? Are the fuel filter and injectors clean?

Maybe the valve clearance for cylinder 5 is too small and one of the valves is not closing completely.

You most likely have an air leak or some cylinders are not firing. I think just one would still allow it to idle. That little way off in the timing chain would still run… Make a video for us after again checking the hoses to avoid embarrassment. :slightly_smiling_face:

The engine is okay and you’re not selling it.

Or maybe a valve was bent during the repair process?

With the compression slightly down it is very possible, after all the crank was not aligned. But it should still run, especially since it is only 20% out on the compression results and not a dead cylinder (which could still run, rough). Correct?

Agreed: the quoted pressures are adequate to get it running.

That is what I’m worried about, I’m going to give it one last shot and then give up and try again with another engine,

doing the head gasket the first time I was overwhelmed but I think It will be much easier to do it a second time but now I have to tackle engine replacement for the first time

I don’t think you are anywhere near the point where you should consider an engine replacement.
You could possibly get a spare engine for parts of it if cheap, but bent valves are easy to replace.
Check everything else before removing the head though.