Trying to remain proud owner of a 1991 Toyota Cressida GLX

[Bill Kearney]

Hi everyone

Posting this with my dad. His pride and joy is his Cressida which may finally have reached the end of the road as its head gasket is 'beyond repair' and no luck in sourcing replacement part or another engine....we are in NZ and at the moment we are facing dad having to decide it's the end of the road for his beloved Cressida...does anyone else have any other advice or suggestions for saving my dad's car? It's in great condition in all other respects, but I gather BHG are a recurring problem for this model....I would hate wrecking the car to be the only option so trying to tap into community expertise...

Thanks for any help/advice you might have and sorry if this is not the right forum, we're desperate!

 

[KAA]

Hi Bill and welcome to the forum, I know the feeling of losing a wonderful car like a Cressida, we had one for about 5 years and loved it, have you tried Australia for the parts required? there are many larger suppliers here that may be able to track down either the gaskets and parts or perhaps a motor. Sad to say it but it may end up being a lost cause I hope not but in the end it could be a very expensive exercise the only other option may be a replacement engine that will fit I am sure any who can comment with ideas will do so, as many on here are diehard Toyota lovers

Good Luck

KAA

[Tony Prodigy]

Hi Bill, don't give up yet. If the car has sentimental value, park it up, cover it up and preserve it until you can figure this out. Don't make any hasty decisions yet, especially wrecking it. These cars are becoming quite rare these days and it would be worth saving for sure. The 1991 Cressida was one of my favourite cars from that era. Always loved the shape and the silky smooth straight 6.

If it's just a head gasket, are you not able to find a decent mechanic to carry out the necessary repairs ? What exactly is the hold up ? You mean to say that you can't find a gasket ?

Are either you or Dad into DIY ? Why not tackle it together ?

Hang in there mate and please don't part the car out. I'd keep it whole and try get it sorted.

[Bill Kearney]

Thank you for the replies KAA and Tony, much appreciated! We will have a look in Australia to see if we can source the parts - I got it wrong, apparently is it a cylinder head which is beyond repair and our mechanic has searched NZ for a replacement without success. Similarly he cannot find a second hand engine either. The car does mean a lot to my dad so I think we may try to bring it back home, put it under cover and see whether we can find a solution. I don't think we could bear to have it broken up.

Any ideas for starting search for a replacement cylinder head in Australia?

Thanks again!

Bill and Angie

[Tony Prodigy]

Not sure where you could find a spare cylinder head or engine, but will keep an eye out for you for sure. It may even pay to look for a spare car if that's even possible.

[KAA]

Bill your most welcome, as Tony said don't throw it in and part it out, is the head cracked? I am sure somewhere there would be a head I also will keep an eye out for any contacts I have. I would do a google search for Australian Parts suppliers, there are many many suppliers for old vehicles, also I would suggest if you do have a good mechanic get a list of all parts needed as it will help with your search have all the vin numbers model numbers etc listed as well 

We are always happy to throw our 2 cents worth in to help in any way we can mate

KAA

[campbeam]

Located this URL which might be useful

https://toyrolla.com.au/toyota-car-parts-7m-ge-7m-gte/ 

 

[Ed.]

dunno if you still have the cressida or not, but if the head isn't cracked, take it to an engine or performance shop. don't take it to a regular machine shop; they will want to mill the head which will remove too much material and is irreversible. Engine/race shops will ground/lap the head, which only cleans the surface and leaves a much better finish.

These engines blow gaskets left and right due to undertorqued factory bolts. People say to get a metal head gasket and yes that'll fix the problem, but it is VERY overkill for a naturally aspirated engine. The oem graphite/composite gasket is perfectly fine. Metal head gaskets require a near mirror-like finish on both the head and the block...this will be very expensive if you can't take it out yourself. Comp gasket is perfectly fine, only requires cleaning the head and you can prep and clean the block while it's in the car. I bought an ishino stone gasket VRS kit on ebay from some british dude, part number is 04111-42033. Ishino sells it under the name Stone, they are the OEM supplier for toyota gaskets.

The main thing is to ensure that the gasket mating surfaces are clean, flat and straight. They do NOT need to look super shiny, the gasket doesn't care what the surface looks like, only that it is clean, flat and straight. When you take the head to the shop, ask them to check for straightness, and confirm that they will ground/lap the head and not mill it. They should straighten the head before doing any grinding or cutting, because a warped head will straighten itself out when hot. If a warped head was milled flat and then put on an engine, the heat during operation would unstraighten it.

If you are going to clean the block while it's in the car, use a razor blade held as flat as possible, and with light finger pressure, scrape off any old gasket debris and dirt. Then use a flat sanding block with 200 grit sandpaper then increase to 400, 600 etc. Again, the surface doesn't need to be as shiny as Karl Pilkington's head, just needs to be clean, flat and straight. I didn't even bother using sandpaper on mine because the areas where the sealing rings for the pistons, coolant and oil passages sit were all clean, flat and straight.

This is also a good time to helicoil the exhaust manifold holes; the studs tend to back out with the nuts and when you try to torque them up, the head has annealed enough that the studs can't hold the torque and end up stripping the threads. Even if some studs are still on the head, get the shop to helicoil all of them, prevention is better than the cure.

If you feel like it, the following are things you can do for a bit of extra power, and improving the reliability of the engine, these are just "while you're there" sorts of things:

- drill out a coolant port in the rear of the head. The block has a coolant port there but for whatever reason, toyota didn't make one in the head. Cylinder 6 tends to go first and this may potentially prevent that. There is even a hole in the actual head gasket itself for that coolant port, and if you look at the head, you might actually see dirt/residue from the coolant that pooled there, which can make a nice guide if you drill out the hole yourself (drill 10mm deep). You can ask the shop to match up the hole in the gasket if you don't feel confident doing this yourself. Some people just drill a few small holes in that area, other people make it the size of the full gasket hole. Main goal is to just get more coolant flowing through there.

- 3 angle valve job on all intake and exhaust ports, assuming it didn't come like that from the factory. This will help improve air flow into the combustion chamber, combined with a 30 degree back cut on the intake valves only, it'll mean a bit more power to keep up with daily traffic. These engines are otherwise great, but they're more than 30 years old at this point. 3 angle valve job and backcut on the intake valves allow the air to flow much more smoothly (and thus quickly) into the chamber, resulting in a slight power gain.

End of engine mods. When putting the head back on, you can use the factory bolts (the repair manual does NOT state them to be single-use items) or get ARP head studs to bulletproof the engine even further. It might actually be overkill to be honest. But whichever route you go, torque the head bolts up to at least 100 N m/75 ft-lb. The factory value of 78 N m/58 ft-lb is not tight enough, and will result in another blown head gasket soon. ARP studs state to torque to 108 N m/80 ft-lb using their specific assembly lube.

After about 1000 km or so, replace the oil and flush the coolant as the oil and coolant would definitely have all the crap floating around from scraping the head gasket. Take off the valve covers and retorque the head bolts/nuts. Back it off a quarter of a turn, then retorque to whatever number you torqued them to prior.

You may also want to talk to people who have MkIII supras with the 7M engine, they had to go through a lot of the stuff you're going through now. I'm going through it too as I type this lol. my cylinder head is currently at a shop with all the stuff I mentioned above.

Edited April 23, 2022 by Ed.