chain reaction

[Jango_Fett]

I just put trd 0.8 head gasket in my 4age and now con-rods bearings are gone
engine was a bit tired (400 000 km) but was running great before this.
now I wonder what is next?

[Jimmi The Kid]

Pistonrings

[sergiocharged]

Jango_Fett Wrote:I just put trd 0.8 head gasket in my 4age and now con-rods bearings are gone
engine was a bit tired (400 000 km) but was running great before this.
now I wonder what is next?

as far i understood
400 000km a bit?
wow
and you just changed the gasket and you asumed putting a 0.8 will increase just a bit the piston m/s velocity?
well man

try to just replace and hopefully not machining,
test pressure and compression ,flat rule the head again,try to replace any part you can change of the head,put a new gasket the right 1 and hopefully everything is gonna be ok and as before
and btw test your rods with a experienced senior with the proper tool just in case.

OR maybe im wrong and just replace the bearings and rev up your engine again to 8200rpm

[Jango_Fett]

I did change head gasket but only because old one had a little leak and recently OMV started to sell 100 octane fuel on their gas stations(only clean fuel you can buy in BiH,the rest is more horse piss than petrol) so I went for trd gasket.
400000 km is a lot but engine had no leeks at all, no smoke from exhaust, compression was spot on in all 4 cylinders and I am a little surprised that my 4age could not take some extra stress. especially after I am told everybody that my rolla is indestructible and I always make fun of my friends who drive french cars

[jasper]

why not change the rod bearings when changing the headgasked??

now you killed the crank

[Bean]

well your CR is probably around 10.8:1, assuming you have the 10:1 pistons... and when you changed the headgasket you had to remove the timing belt and distributor I guess.. so was everything set up properly again? ignition timing, timing belt, etc... the camtiming will be out a tad anyway due to the thinner headgasket... maybe down to inproper install you pushed dynamic CR through the roof and therefor putting too much load on the old bearings... alternativly down to increased piston speed the rodbolt sufferd (they aren't the strongest to begin with, especialy at high rpm) and allowed a bit too much play in the bearings and they died 'cause of that.

[Jimmi The Kid]

Did you change the oil after you finish the gasket job? When you remove the cyllinderhead, water will run down in the oil and water are heavier than oil and will sink to the bottom of the oilpan. The oilpump will then such water insted of oil and the bearings will worn out.

Change the bearings and if you are lucky, crank have survived. I busted my bearings 2 times on my 20V Silvertop @ 9500 rpm and drow 50km home and changed the bearings. Crank did not take any damage.

[Jango_Fett]

finally, bearings arrived and my rolla is on the road again
crankshaft is ok, no damage at all, but engine is getting grumpy like a old man and it is telling me that is time for full rebuild
meanwhile I found 2 redtop engines for 350 euros
since they are in good condition (based on condition of the cars they came from) and cheap , I decided to use this extra money and squeeze some extra power.
my question is : what would you do in my situation ?
any advice is more than welcome

thanks

[NoHachi]

Crank bearing failure is almost 99% oil related.. Maybe it was water in the oil, or maybe you have a failing oil pump or other problem. Whatever it was, it was not due to the higher compression.
I would change all those things on your replacement blocks first before diverting money to small power increases.