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David
10-02-2013, 02:58 PM
Anybody, My 94 previa blew the head gasket so I was able to pull the head without pulling the engine ( thanks to Tim ) but I forgot about the timing chain tensioner and I broke the front part of the chain damper, so, my question is, can I remove the timing case cover without dropping the engine? Thanks.

Previa dude
10-11-2013, 01:36 AM
Yes. You can. You will have to lower it about 6 inches to do so though.

David
10-11-2013, 07:11 AM
Thanks, I appreicate your help.

shaddart
05-10-2015, 09:25 PM
Hi, 95 Previa 2wd S/C -

In process of removing head to do head gasket-

Found pieces of timing chain damper/slipper in oil pan

Need to replace them and maybe the whole timing set.

Can I do it with engine still in vehicle?

The FSM says I need to remove the crank case, but there are two bolts that look like they are under the flange of the transmission (the two rear ones)

Has anyone done it?

thanks.

Paul

timsrv
05-11-2015, 04:27 AM
If you've got the engine low enough to remove head, it should be low enough to do the timing cover. I've heard of doing this without completely removing the engine, but I can't help wonder why this would be attempted. By the time you get the engine low enough to do this work, it's practically out, so why not drop it the rest of the way for complete access? In my opinion you're wasting time by trying to save it, but I could be wrong (as I've never attempted or even considered doing the job without 1st completely removing the engine). Tim

shaddart
05-11-2015, 05:12 AM
Ok sorry, more info :

I did the trick of jacking up the engine, removing the motor mounts, and lowering it down those couple inches onto wood scraps, to gain a little more access to the nuts and bolts on the intake manifold, etc. I am not lowering the motor down from the chassis.

I don't have the equipment to remove the whole motor, or else I would go the JDM engine swap route, which would be awesome.

The FSM says I need to remove the crank case to be able to remove the timing chain cover.

It looks like the rear most bolts of the crankcase are obstructed by the transmission.

So I was hoping someone had completed / attempted this on a Previa and could tell me if it is possible.

I'll try to get a pic after work.

Thanks.

shaddart
05-12-2015, 07:01 PM
2440

timsrv
05-13-2015, 01:28 AM
Remove the starter and that transmission bracket. There's another bracket under the starter, then you can remove that inspection plate.

shaddart
05-13-2015, 02:08 AM
Thanks! :doh:

Now, I get it, the "torque convertor clutch cover"- My mind wasn't seeing that because in the diagram it says "4WD" next to it, so I kind of ignored it.
I knew about taking off the starter but I need to use that to remove the crank pulley bolt (breaker bar against frame, I hope, ha ha) so didn't want to remove it yet.

Does anyone know if I have to completely remove the accessory drive shaft to remove the main crank pulley or can I just disconnect it at the engine and nudge it away?

thanks for you patience, people.

Paul

PS I am thinking of scrapping this van- I only paid $400 for it and the more I mess with it the more signs of neglect I find (205k miles)- he said he didn't do oil changes or "hardly ever), the belts are badly cracked, super charger belt completely missing, most rubber engine hoses hard as a rock, etc.

I could replace the head but then would the rings get worse, etc.... unfortunately I never saw or heard it running.....

just thinking out loud...... there are some pretty nice Previas for sale within and hour or two of me- some have sun/moon roofs and one only has
122k on the engine.

My daughter's like, "maybe it would be better to buy one that is already running" ha ha. :roflmao: silly girl.

I enjoy a challenge, and the head gasket job seemed barely tolerable, but things are getting more intense.

Any advice appreciated. Thanks for the replies.

timsrv
05-13-2015, 02:36 AM
Regarding the SADS, it's okay to leave the shaft there and "nudge" as required, but don't let it hang or keep it in a position unnatural to where it would normally be. Whenever it's disconnected from the crankshaft pulley it needs to be supported (wire ties, a coat hanger, or whatever works). Leaving it hang or keeping a constant "preload" on the rubber bushings can cause them to tear. With that many miles I'd have to assume the flex couplers are already shot, so if you're going to replace them anyhow, I guess you could disregard the above mentioned handling suggestions.

As for whether or not this is the right Previa for you is a personal decision. Personally I like saving things that would otherwise be junked. I get more enjoyment out of these vehicles, but I'll admit they can be time & money wasters. From an economic stand point, it probably makes more sense to find something that already runs, but anything this old with higher miles will eventually need repairs. If you plan on keeping long term, then it will all come out in the wash (the work you do now will pay off over a long term relationship). If you take care of everything now, there's less to worry about later.

I've learned from experience to avoid things that were neglected or otherwise abused (the lack of oil change comment would have turned me off). Unless you were swapping engines with a JDM or going for a complete tear-down/reworking of the existing engine, I probably would have avoided that one (been there done that). But, it sounds like you're already into it up to your eyeballs, so at this point I'd probably keep my nose to the grindstone & make the best of it. Tim

PS: I've heard it said that fixing top end issues can stress & create low end issues (cause rings to blow out, etc). I personally disregard such claims. On the Previa however, considering the labor to remove the head (in my opinion the engine should be removed), & based on the other work you need to do, I would probably would have elected to tear down the entire engine and do rings & bearings too. Tim