cressida RX30 engine problems

[MarkIIRx12]

Hi

I just bought myself a 1977 cressida coupe, it has a 18R in it.

The engine runs fine except it makes some strange noise, the engine i been told have run over 320 000km, so im guessing the sound im hearing is from the timing chain, although i never heard of this problem on a 18R before. the engine have been sitting for at least 5 years tho, and the owner said this noise wasnt there when he parked the car, so can it be a oil problem or something? does this engine have hydraulic timing tensioner? any other suggestion what causes this problem?

The sound sounds like its coming from the timing tho, but im not 100% sure, at first i thought it maybe was the valves, but they are not hydraulic either are they?

anyway i need to take off the timing cover, cuz it leaks a lot of oil from there, so to problem number two; i been searching for gasket sets and timing chains on ebay, and other stores in the usa, but all the 18R's there seems to stop at 1974, i guess maybe this was the last year this engine was sold there, but im not sure.

Could anyone confirm if a 1977 18R uses the same gaskets and timing chains as a 1974 or earlier one? or can anyone confirm they are diffrent?

Cept for the engine problems, its really a great car, i love this coupe already, i will add some pictures of it later when im finished working on it.

Thanks in advance for your help

[gianttomato]

The engine runs fine except it makes some strange noise, the engine i been told have run over 320 000km, so im guessing the sound im hearing is from the timing chain, although i never heard of this problem on a 18R before.

Have you been living in a cave? Standard fare - timing chain looks real pretty when it smashes the timing cover. Could be the tensioner though - might be gummed up if it hasn't run for 5 years.
Oh yeah - pix now - we never got the coupe.

Keep searching ebay - there was a set of gaskets on ebay australia recently.

Here's one:http://cgi.ebay.com.au/TOYOTA-HILUX-...QQcmdZViewItem

[schnitzel]

Early and late 18r's have different heads. however most gaskets interchange. Believe the chains are the same but don't know for sure. I would be checking tensioner first, as said is probably sticky. Have you changed the oil? that would be a good start.

[MarkIIRx12]

Hi again

Thanks for ur answers.

i havent changed the oil yet, since the engine is leaking a lot, i was thinking i better take care of that first.

Is there a way i can acsess the tensioner without taking off the covers? i opened 2 19mm screws, and inside one of them it was a spring, and inside the other it was a pointed thingy that kinda looked like the tensioner cept it was very short. is there anything i can do to manually adjust the tensioner, or at least check if its working? does it have one or two tensioners, and one or two chains?

I looked at my 1973 18R and this seems to have a smaller timing cover, im wondering if it maybe have a smaller chain too.

Does anyone have partnumbers for the chains, tensioners, timingcover and valve cover gaskets and could check if they are the same?

Thanks again for your help

[o_man_ra23]

Pic of the engine would be a good start. Later 18Rs I have had a lot to do with. The 19mm bolts you pulled are the upper tensioner assembly (cant remember exactly how they work, will look when I get home tonight). The horizontal one will have the spring, and a plunger that is probably still inside the engine. This plunger pushes on the upper tensioner slipper which pivots inside the timing case. There is a lower tensioner also, and you must pull the timing cover off to get to it.

Only way to seal the leak in your timing cover (if its at the top) is to replace the head gasket. When you do, make sure you use plenty of good quality silicone sealant on the bit that extends over the timing cover. I have tried many times to seal these, and unfortunately head gasket replacement is the only way.

After time, used engine oil goes acidic, good to replace it regardless of leaks. Just buy a cheap bottle of oil, as it will help to flush all of the old stuff out before you go putting expensive stuff in.

[MarkIIRx12]

Thanks for ur answer.

i can take a picture of the engine, but im not sure u will be able to see much since its soaked in oil.

can i use a screwdriver inside the upper tensioners hole, and try to push it further in to see if the noise gets better then, or can something bad happen if i do that?

its kinda hard to see where the leaking comes from, but it can look like its from the buttom of the cover, or maybe the crank seal? i really have to take the head off to get it sealed? i was really hoping to avoid that.

Since u been dealing with theese newer engines, do u know if the cover gaskets and chains are the same as on the older engines?

[o_man_ra23]

Never touched the older engines sorry. You say you cant find the leak... well the very first step is to clean the engine (you will need to put the tensioner assembly back together). Once the engine is clean you can look for the leak. Once you know where the leak is, you can fix it.

If its the front pulley seal, then you just need to remove the front pulley, pop the seal out, put another in and put the seal back on... piece of cake.

If you leave the plunger in place, you should be able to push the tensioner in. Dont push too hard though as the slipper surface material may have gone brittle and could well disintegrate with too much force (usually fine under normal spring pressure though... never seen a catastrophic failure like that)

Twice I have had engines with really bad rattles. One had a broken valve spring, and it was only the inner dampner spring that kept the valve from falling in. The other the pivot of the upper tensioner slipper broke, and the upper tensioner slipper was just dangling around inside... lucky it didnt break a chain or similar.

[MarkIIRx12]

Hi again

Hmm, the noise isnt that bad, i have heard worse from opel/vauxhall and thoose engines, so i dont think anything have broken yet, but the noise is there constantly, so i assume i better fix it before it gets worse.

havent gotten around to start it again yet, im putting in the new black interior theese days, and will start looking more at the leaking and stuff during the next days.

Do u happen to have any part numbers for the chains for the newer engines, or know of a place online they have it?

Do you have a workshop manual on this engine or do u just have it all memorized?

Thanks again for ur help

[thechuckster]

i have an 18R engine manual at home - but there's a few threads here (somewhere) on 18R chain tensioners. There's some cross compatibility between various bits of the tensioning system with 18R and others (5MEs come to mind).

The spring on the upper chain tensioner should be pretty long - it fits over a small stub on the end of the bolt and pushes the tensioner block up against the upper chain - if the spring is short then find another. That tensioner also gets oil pressure for the oil line the block going up the front cam cap so as you reve the engine it 'should' put more pressure on the upper chain.

Not sure about the lower spring - but the 18RG kids here should have advice.

if it's making noise 100% of the time, i'd suggest repair time before the chain exits the allow cover at a great rate of knots.

[o_man_ra23]

Lower spring unit comes as a bolt on item with slipper, about $20 last time I bought one.

Parts should be available aftermarket from any parts shop.

[thechuckster]

but in virginia, USA?

is the 18R covered by folks like Autozone?

[gianttomato]

www.rockauto.com also very good - USA based. I use it for specs sometimes.

[o_man_ra23]

Just looking in my 71-78 Celica ST/GT USA spec manual... They have no mention of early and late 18Rs... instead they mention the 8R and 18R as being the earlier and later engines (respectively). You sure your earlier motor isnt an 8R?? which was a smaller capacity but had greater power and torque (18R suffered emmissions laws)

Anyways, that manual also shows a different upper tensioner setup, which works in much the same way as the lower tensioner, and negates the 19mm bolts that you removed (ie, the head doesnt have them), and also does not have the pivoting upper tensioner slipper, so there is no stud protruding out the front of the timing cover.

The other manual I have, which covers LT models, shows the other type with the swinging upper slipper. This shows that the bolt with the pin coming out of it has a washer, and a spring actuating on the tensioner plunger. This inserts horizontally. The other 19mm bolt is inserted vertically. I would hazard a guess that this is a hollow bolt and allows the oil to pressurise in (will pull the one off my spare head on the weekend and check)

So yeah, first thing to do is clean it, second, drain the oil and put in some cheap stuff, third run it and find the leak, four is to fix the leak, five is to fill with new oil and new filter and drive... Good luck

[thechuckster]

owen: yup - the vertical bolt has a restrictor in it otherwise you loose too much oil pressure at the head and the cam journals would wear out prematurely. I think it also something of a one-way valve in it as well.