420a Rebuild - Ongoing Advice

[Luke Home]

New Thread ... I have looked and search this forum for the needed info on rebuilding a 420a motor with only finding threads that seem to lead me into the wrong areas of this forum and thus posting with rebukes. So this new thread.

Back ground info:
I have a 1997 EAGLE TALON ESI, 2.0L L4 SFI DOHC 16V (420a) motor. This motor/trans has 140K on it. I pulled the motor/trans together and now I am ready to fix the problem. The original problem is this: The idler pulley (for the timing belt) bearings blow up and hence trashed the belt which bent a valve or two (as far as I can tell at this time). I removed the trans from the block and I am trying to get the torque converter off but the crack will only turn about 220 degrees or so. I would like to get the torque converter off so I can get this block on an engine stand. I am assuming I will need to remove the head first before I will be able to turn the crank enough to get the last two torque converter bolts out. I have rebuilt a few motors in my day and would like to ask those here for their answers to questions that are specific to this motor and or similar motors that may prove to benefit this project. Like:

1.) What manual is the best manual to purchase which will have the needed specs for this 420a motor? Or is it downloadable from the internet, would someone please share the URL?
2.) Are there particular parts (brand names) I should be using over parts purchased from, lets say NAPA? Like gaskets, Belts, Bearings, Valves, etc.
3.) What links have the experienced ones here found to be the best place to purchase parts for rebuilding … such that it will keep the cost to a minimum but would give me a good stock motor? Hopefully one that would make another 100K.
4.) Any idiosyncrasies about this motor/head that would be of benefit to the over hauling of this motor?


I expect to be adding questions/comments/pictures to this thread in the days and weeks ahead until this project is complete so patients with the elementary questions would be greatly appreciated.

Thanks,

[xavier3jr]

Haynes manuel is the best period thats what i used has ever torq spec and all instructions.

Felpro gaskets are the best for the money IMO very good gasket

ONly use OEM TBelt go to dealer ship


as for pistons rods ect your option if you want more power go with some aftermarket shit if you want a stop motor but stock pistons

[defiancy]

Use ARP Studs and Clevite bearings if possible, even if you are not doing a performance related build. These parts cost a little more but they are definatley worth it.

[Luke Home]

Originally Posted by defiancy

Use ARP Studs and Clevite bearings if possible, even if you are not doing a performance related build. These parts cost a little more but they are definatley worth it.

Do these Head Bolts need to be replaced every time the head is removed? Are these call "Stretch Bolts"?

Ok ... I got the head off and what looks like all the Intake Valves are bent. Why would only the intake valves get bent and none of the exhaust valves? Is this motor designed to have piston to valve clearance (at TDC, valves open) for the Exhaust Valves only?

One more onging question: please check this picture out
Link
Is this timing belt Pulley tensioner item spring loaded or what? I tried to compress this shaft on the work bench and it will not move. I even tapped it with a hammer ... with no movement. Is this as designed?

Next step is to get it on a engine stand and check out the crank shaft and bearings.

[david-b]

Originally Posted by Luke Home

One more onging question: please check this picture out
Link
Is this timing belt Pulley tensioner item spring loaded or what? I tried to compress this shaft on the work bench and it will not move. I even tapped it with a hammer ... with no movement. Is this as designed?

It's hydraulic. It's a bitch to compress but it's doable. Yes it's supposed to be like that. That makes the tension on the timing belt. The TB moves around, so you want something that's not going to move right? It's mad to be like that. Use a little WD40 and let it soak a little, then use a big vice or c-clamp and it'll go. First time is the hardest since it hasn't been moved since factory more than likely. But after that (if you mess up putting it back) it's not that hard then.

[gthompson97]

Yes, the head bolts are TTY, torque to yield. Clevite bearings are good, and Fel-Pro gaskets are good too. Actually, everything said above is correct.

[Luke Home]

Question:

Can someone point me to the brand (name) or link
to a Valve Spring compression tool for the valves on this head. The one I have (which I used on the engines I overhauled by in the 80s will not work).

These valve springs look like they have very little room for any tool.

Also, I am waiting on a HAYNES MANUAL I purchased for engine specs.

Whats is the max. oil clearance allowed for the Crank-to-Rod bearings and Main Crank bearings?

I just checked the Crank-to-Rod bearings tonight and I am getting .0015" to .0017".

Thanks....

[Talon69]

unbelievable

[gthompson97]

They don't make a consumer based valve spring compressor for our cars, you either have to make one (like 99% of us do, I used a socket and a c-clamp with a hole notched in the side to get to the spring retainers), or buy one from the dealer for an arm and a leg. You definitely need to do some searching though, your questions are very general and can be answered in many different places in the forum. IIRC, .0015 is a general max clearance for a crank-rod bearing clearance, but I can't remember specifically what our cars are, and I'm too lazy/tired to look it up.

[david-b]

I recommend going to a hardware store and picking up a piece of piping and a large C-Clamp. The piping needs to be a T pipe and you just do some trimming til it fits.

Actually here's a pic. Piece cost like $.69 or something like that. It's brass so it's solid and has a hole in the middle where you can get to the lock.

[Luke Home]

Originally Posted by david-b

I recommend ....

This is cool! That is certainly using the creative side of the mind and the cost is perfect! Thanks for sharing ... this will indeed be my need tool added to my arsenal.

[Luke Home]

Originally Posted by gthompson97

They don't make a consumer based valve spring compressor for our cars.....

You definitely need to do some searching though....

Now, for someone who has never worked on these motors before and is seeking advice from the people who have ... like on a forum such as this ... how would I have known that unless someone like yourself was willing to share. I have spent many hours pouring through posts on this forum for insight into working with/rebuilding/repairing this motor. Then when I find something from a older post and reply to it to get more clarification ... I either get rebuked because I am in the wrong part of the forum with such a question or advised that the post is old and/or I get some remark that has nothing to do with the orginial post or the question I asked. Now if this forum is for the experience motor heads only ... then please advise me of that and I will try to find another source to get my general (or not so general) questions answered. I am not trying to be red here, I am just trying play within the guild lines of the forum and get real replies that may bring me up-to a speed that is not so general as well as get this motor rebuild correctly without taking it to someone to do it. I am sure many of you were at the same point at one time or another.

Hence, that is why I started this thread. If some of the questions are too elementary for the experience people on this forum, who may have forgotten what it was like NOT to be so experienced, please just overlook my ignorance and go on to the next thread.

But I need your help and that is why I am here. And by the way ... THANK YOU all who are willing to help out with usable info and replies.

Luke

[david-b]

You're completely right about this.

But about the old threads thing, just let them die. They're old for a reason. If you want to comment on something like that, make a new thread in the proper forum and quote/link to the old thread and ask for clarification or whatever.

This forum is definitley not for hard-core motor heads, but a simple manual (like you asked about in the first post) would have answered a couple questions. That's why the first thing you should buy with any car is the manual for it. Just good reference.

We're willing to help you the whole way, so don't think we're steering you away. We all want to share knowledge with others, and ya some people can be dicks. But just ignore that.

And for reference with that copper pipe setup, I didn't have that when I took the springs/valves off, and it took a long time. When I rebuilt the head and put it all together, it took at most 10 minutes to put together, compress, and get the locks on there with grease and all. Well worth it IMO. Just try to match the size of the pipe a lil smaller than the retainer. Or, just reshape to fit. I had to trim my piece quite a bit to properly fit the whole way, but very easy. Good luck.

[gthompson97]

Wasn't trying to be a dick, it was late and I was tired. I apologize if i came off that way.

Anyways, the main bearing oil clearance is .0008" -.0024". The rod bearing oil clearance is .0010" - .0023", so it looks like you're rod bearings are right in the middle which are good to run, what'd you measure the mains at? Also, standard crank end play is .004" - .009" with the limit being .015", in case you want to measure that.

[Luke Home]

Originally Posted by david-b

... but a simple manual (like you asked about in the first post) would have answered a couple questions. That's why the first thing you should buy with any car is the manual for it. Just good reference.
...

Thanks .... I do have a manual coming and I knew that the question I asked would have been answered in the manual ... I just got a little inpatient waiting.

I will try to exercise more discipline in the days ahead.

I haven't checked the main bearings yet. Hope to get to that soon.