2004 And No Compression :(

June 4, 2009

Bad news today. After what I thought was an overheating incident, I was informed by the dealership and a 2nd mechanic that my 2004 Rav4 AWD Sport has no engine compression. :angry: 96k miles.

Everyone I've talked to about this says it was a "freak" occurrence. Every scheduled maintenance performed and oil levels fine.

One of the reasons I was a fan of it was the timing chain, not belt, and was hoping for more reliability. (i've had engines replaced in the past)

No one wants to start taking it apart yet, due to labor. The best recommendations I get are to just drop in a used engine. One place has quote me $4500 P&L for a 30k used engine. I'm calling for other quotes now and possibly may get it down to $3000.

Two questions:

What would you do? Scrap er'? Minimal trade-in?

What is a reasonable price for a salvage engine for this make/model?

June 4, 2009

i'm sorry. i just noticed this was a UK forum.

June 4, 2009

i'm sorry. i just noticed this was a UK forum.

Hey, don't apologise. All are welcome here!

You may even get some advice :thumbsup:

June 5, 2009

Hi...

First thing I would do is to whip the head off and check out the reason for the lack of compression! That should not be too expensive (others on here can probably quote on that). You may be lucky and just get away with a new head gasket + a head/block skim! It would be useful to know if it is just one cylinder that is low compression or an adjacent pair or all of them?

If you have had engines 'go' on you before... you may want to examine your driving style! There is an optimum engine rev range when driving to preserve the life of an engine.

I hope you manage to repair your Rav 4 without too much expense.

All the best... DaveH

June 7, 2009

You can get an idea of where the problem lies (to a certain extent) without removing the head. You need to do a compression test and the results should point you in the right direction;

If the test shows low/no compression (which sounds likely according to your post) then you need to pour a little oil down each spark plug hole and then do the test again. If the results improve, then the piston rings are the problem. If the results don't improve then the problem is that the valves aren't sealing. If the test shows that two adjacent cylinders are reading low then the headgasket is probably gone.

If the rings are gone, then a re-con engine may be your best bet. If the valves aren't sealing then you need a new head. If the head gasket is gone, that is a relatively straightforward job.

June 8, 2009

Some good pointers in the last post... however, when I was in the motor trade (ok, I admit it was long time ago!), we used to 'fix' things! If the rings had broken/worn out we used to hone or rebore the cylinders, then fit new rings or even over size piston/rings if required. If the valves were not seating... then new valves and or new valve seats could be inserted. Replacing a short block or new head was considered a last act of desperation... and usually only if the head or block was cracked; it was also normally the most expensive option!

I know we live in a throw away society, but surely a quality engine as fitted to a Toyota can be repaired still? Anyhow, I hope I never have to find out! :eek:

DaveH (ex-mechanic, Lotus, Ford (Ford Sport), Rover, Vauxhall and Jaguar) Aghhhh, them were the days! :rolleyes:

You can get an idea of where the problem lies (to a certain extent) without removing the head. You need to do a compression test and the results should point you in the right direction;
If the test shows low/no compression (which sounds likely according to your post) then you need to pour a little oil down each spark plug hole and then do the test again. If the results improve, then the piston rings are the problem. If the results don't improve then the problem is that the valves aren't sealing. If the test shows that two adjacent cylinders are reading low then the headgasket is probably gone.
If the rings are gone, then a re-con engine may be your best bet. If the valves aren't sealing then you need a new head. If the head gasket is gone, that is a relatively straightforward job.